Uplink control channel for acknowledging increased number of downlink component carriers

ABSTRACT

Techniques are described for wireless communication. One method includes determining, based at least in part on a number of downlink component carriers (CCs) scheduled for a user equipment (UE) during a reporting interval, a number of bits to be included in a physical uplink control channel (PUCCH) acknowledgement/non-acknowledgement (ACK/NAK) payload for the reporting interval; and selecting, based at least in part on the determined number of bits, a format of the PUCCH ACK/NAK payload.

CROSS REFERENCES

The present application for Patent claims priority to U.S. ProvisionalPatent Application No. 62/110,307 by Gaal et al., entitled “UplinkControl Channel For Acknowledging Increased Number Of Downlink ComponentCarriers,” filed Jan. 30, 2015, assigned to the assignee hereof, andexpressly incorporated by reference herein.

BACKGROUND

1. Field of the Disclosure

The present disclosure, for example, relates to wireless communicationsystems, and more particularly to techniques for increasing the numberof downlink component carriers that can be acknowledged (ACK'd) ornon-acknowledged (NAK'd) in a payload of an uplink control channel.

2. Description of Related Art

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems,single-carrier frequency-division multiple access (SC-FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

By way of example, a wireless multiple-access communication system mayinclude a number of base stations, each simultaneously supportingcommunication for multiple communication devices, otherwise known asuser equipment (UEs). A base station may communicate with UEs ondownlink channels (e.g., for transmissions from a base station to a UE)and uplink channels (e.g., for transmissions from a UE to a basestation).

In some modes of operation, a UE may operate in a carrier aggregationmode or dual-connectivity mode, in which the UE may be configured tocommunicate with one or more base stations using a plurality ofcomponent carriers. When receiving transmissions over a plurality ofdownlink component carriers, a UE may use a payload of an uplink controlchannel to ACK or NAK receipt of the transmissions.

SUMMARY

The present disclosure, for example, relates to one or more techniquesfor increasing the number of downlink component carriers that can beacknowledged or non-acknowledged in a payload of an uplink controlchannel. With increases in the spectrum available for Long TermEvolution (LTE) communications or LTE-Advanced (LTE-A) communications(LTE/LTE-A communications), and in some cases increases in thegranularity of available spectrum, the number of component carriers overwhich a UE can simultaneously communicate is being increased. However,the format of the physical uplink control channel (PUCCH) ACK/NAKpayload used in LTE/LTE-A systems has limited ACK/NAK capacity. Althoughtechniques can be used to increase the ACK/NAK capacity, there are timeswhen a UE may simultaneously communicate over fewer than 32 componentcarriers (and possibly even fewer than five component carriers). Astatic PUCCH ACK/NAK payload format that provides capacity foracknowledging/non-acknowledging transmissions over a maximum number ofcomponent carriers may therefore be wasteful when fewer than the maximumnumber of component carriers is scheduled. Techniques described in thepresent disclosure provide for selecting a format of a PUCCH ACK/NAKpayload depending on the number of bits to be included in the PUCCHACK/NAK payload. Techniques are also described for ensuring that thePUCCH ACK/NAK payload format selected by a UE is the same PUCCH ACK/NAKpayload format selected (and expected) by a base station.

In a first set of illustrative examples, a method for wirelesscommunication is described. In one configuration, the method may includedetermining, based at least in part on a number of downlink componentcarriers (CCs) scheduled for a user equipment (UE) during a reportinginterval, a number of bits to be included in a physical uplink controlchannel (PUCCH) acknowledgement/non-acknowledgement (ACK/NAK) payloadfor the reporting interval. The method may also include selecting, basedat least in part on the determined number of bits, a format of the PUCCHACK/NAK payload.

In some examples of the method, selecting the format of the PUCCHACK/NAK payload may include selecting one of a plurality of predefinedformats for the PUCCH ACK/NAK payload, wherein the predefined formatsfor the PUCCH ACK/NAK payload include different combinations of: UEmultiplexing densities within a resource block (RB), spreading factors,or numbers of RBs allocated per symbol period. In some of theseexamples, each of the predefined formats for the PUCCH ACK/NAK payloadmay be based at least in part on a format including two reference signalsymbol periods per slot.

In some examples of the method, the selected format of the PUCCH ACK/NAKpayload may be based at least in part on a format including tworeference signal symbol periods per slot. In some examples of themethod, the selected format of the PUCCH ACK/NAK payload may be furtherbased at least in part on a format including one reference signal symbolper slot.

In some examples of the method, selecting the format of the PUCCHACK/NAK payload may include comparing the number of bits to be includedin the PUCCH ACK/NAK payload to a plurality of bit ranges, and selectingthe format of the PUCCH ACK/NAK payload based at least in part on thecomparing. In some examples, the selected format of the PUCCH ACK/NAKpayload may include a UE multiplexing density, within a RB, of at leastfour UEs. In some examples, the selected format of the PUCCH ACK/NAKpayload may include a UE multiplexing density, within a RB, of two UEs,and at least two groups of symbol periods. Each of the at least twogroups of symbol periods may include at least one symbol, and spreadingmay be applied independently within each of the at least two groups ofsymbol periods. In some examples, a spreading factor of three may beapplied to a first group of three symbol periods, a spreading factor oftwo may be applied to a second group of two symbol periods, and two ofthree orthogonal cover codes (OCCs) may be used when applying thespreading factor of three. In some examples, a first spreading factor oftwo may be applied to a first group of one symbol period, a secondspreading factor of two may be applied to a second group of two symbolperiods, and a third spreading factor of two may be applied to a thirdgroup of two symbol periods. In these latter examples, the firstspreading factor may be applied using a Walsh code or using elements ofan orthogonal Fast Fourier Transform (FFT) matrix.

In some examples of the method, each spreading factor of a plurality ofspreading factors of two may be applied to a respective symbol period ofa plurality of symbol periods. In these examples, each spreading factorof the plurality of spreading factors of two may be applied using aWalsh code or using elements of an orthogonal FFT matrix. In someexamples, the selected format of the PUCCH ACK/NAK payload may includeno UE multiplexing within a RB, no spreading factor, and an RBallocation per symbol period of one. In some examples, the selectedformat of the PUCCH ACK/NAK payload may include no UE multiplexingwithin a RB, no spreading factor, and a RB allocation per symbol periodof two. In some examples, the selected format of the PUCCH ACK/NAKpayload may include no UE multiplexing within a RB, no spreading factor,and a RB allocation per symbol period of three.

In some examples, the method may include identifying an allocation of aplurality of downlink CCs for the UE, and identifying a first subset ofdownlink CCs within the plurality of downlink CCs. In these examples,the number of bits to be included in the PUCCH ACK/NAK payload may beidentified for the first subset of downlink CCs. In some examples, thePUCCH ACK/NAK payload may include a first PUCCH ACK/NAK payload, and themethod may include identifying a second subset of downlink CCs withinthe plurality of downlink CCs, where the second subset of downlink CCscorresponds to a second PUCCH ACK/NAK payload. In some examples, themethod may further include transmitting the first PUCCH ACK/NAK payloadon a first uplink CC, and transmitting the second PUCCH ACK/NAK payloadon a second uplink CC. In some examples, the method may further includetransmitting the first PUCCH ACK/NAK payload and the second PUCCHACK/NAK payload on a same uplink CC.

In some examples, the method may include receiving, at the UE, a numberof downlink grants indicating the downlink CCs scheduled for the UE, andreceiving with each of the downlink grants a respective downlinkassignment index (DAI). In some examples, the respective DAI for adownlink grant may indicate a bit mapping and resource selection, in thePUCCH ACK/NAK payload, for acknowledging/non-acknowledging eachtransmission over each downlink CC scheduled in the downlink grant. Insome examples, the respective DAI for a downlink grant may include asequence number indicating a relationship between at least one downlinkCC scheduled in the downlink grant and at least one downlink CCscheduled in another downlink grant. In these latter examples, themethod may include determining, based at least in part on the sequencenumber, a bit mapping and resource selection, in the PUCCH ACK/NAKpayload, for acknowledging/non-acknowledging each transmission over eachdownlink CC scheduled in the downlink grant.

In some examples, the method may include transmitting, from a basestation to the UE, a plurality of downlink grants indicating thedownlink CCs scheduled for the UE, and transmitting a plurality of DAIs.Each of the plurality of downlink grants may include a respective one ofthe DAIs in the plurality of DAIs. In some examples, the plurality ofDAIs may include a plurality of sequence numbers, and the method mayfurther include introducing sequence discontinuities in the plurality ofsequence numbers, to increase the number of bits to be included in thePUCCH ACK/NAK payload. In some examples, the method may further includereceiving the PUCCH ACK/NAK payload, and using a set of ACK/NAK bits inthe PUCCH ACK/NAK payload, which set of ACK/NAK bits correspond to thesequence discontinuities, as a virtual cyclic redundancy check (CRC).

In some examples, the method may include receiving, at the UE, anACK/NAK resource indicator (ARI) identifying at least two differentuplink CCs. In some examples, the method may include receiving, at theUE, a number of downlink grants indicating the downlink CCs scheduledfor the UE; and selecting the format of the PUCCH ACK/NAK payload mayinclude selecting a format used to transmit the PUCCH ACK/NAK payload.In some examples, the method may include transmitting, from a basestation to the UE, a plurality of downlink grants indicating thedownlink CCs scheduled for the UE; and selecting the format of the PUCCHACK/NAK payload may include selecting a format used to decode the PUCCHACK/NAK payload.

In some examples, the method may include configuring at least two groupsof downlink CCs, and selecting the format of the PUCCH ACK/NAK payloadmay be performed for each of the at least two groups of downlink CCs. Insome examples, the method may include configuring at least two groups ofdownlink CCs, and selecting the format of the PUCCH ACK/NAK payload maybe performed considering bundling of ACK/NAK bits for the downlink CCswithin each group of downlink CCs.

In a second set of illustrative examples, an apparatus for wirelesscommunication is described. In one configuration, the apparatus includesmeans for determining, based at least in part on a number of downlinkCCs scheduled for UE during a reporting interval, a number of bits to beincluded in a PUCCH ACK/NAK payload for the reporting interval. Theapparatus may also include means for selecting, based at least in parton the determined number of bits, a format of the PUCCH ACK/NAK payload.In some examples, the apparatus may further include means forimplementing one or more aspects of the method for wirelesscommunication described above with respect to the first set ofillustrative examples.

In a third set of illustrative examples, another apparatus for wirelesscommunication is described. In one configuration, the apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to determine, based at least in part on anumber of downlink CCs scheduled for a UE during a reporting interval, anumber of bits to be included in a PUCCH ACK/NAK payload for thereporting interval. The instructions may also be executable by theprocessor to select, based at least in part on the determined number ofbits, a format of the PUCCH ACK/NAK payload. In some examples, theinstructions may also be executable by the processor to implement one ormore aspects of the method for wireless communication described abovewith respect to the first set of illustrative examples.

In a fourth set of illustrative examples, a computer program productincluding a non-transitory computer-readable medium is described. In oneconfiguration, the non-transitory computer-readable medium may includeinstructions to determine, based at least in part on a number ofdownlink CCs scheduled for a UE during a reporting interval, a number ofbits to be included in a PUCCH ACK/NAK payload for the reportinginterval. The non-transitory computer-readable medium may also includeinstructions to select, based at least in part on the determined numberof bits, a format of the PUCCH ACK/NAK payload. In some examples, thenon-transitory computer-readable medium may also include instructions toimplement one or more aspects of the method for wireless communicationdescribed above with respect to the first set of illustrative examples.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure.

Such equivalent constructions do not depart from the scope of theappended claims. Characteristics of the concepts disclosed herein, boththeir organization and method of operation, together with associatedadvantages will be better understood from the following description whenconsidered in connection with the accompanying figures. Each of thefigures is provided for the purpose of illustration and description, andnot as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an example of a wireless communication system, inaccordance with various aspects of the disclosure;

FIG. 2 shows a wireless communication system in which LTE/LTE-A may bedeployed under different scenarios using a shared radio frequencyspectrum, in accordance with various aspects of the present disclosure;

FIG. 3 shows a wireless communication system in which LTE/LTE-A may bedeployed in a carrier aggregation scenario, in accordance with variousaspects of the present disclosure;

FIG. 4 shows an exemplary resource block (RB) of a PUCCH, which RB maybe transmitted or received during a subframe, in accordance with variousaspects of the present disclosure;

FIG. 5 shows an exemplary RB of a PUCCH, which RB may be transmitted orreceived during a subframe, in accordance with various aspects of thepresent disclosure;

FIG. 6 shows an exemplary table of predetermined formats of a PUCCHACK/NAK payload, from which a format of a PUCCH ACK/NAK payload may beselected by a UE or base station, for a reporting interval, inaccordance with various aspects of the present disclosure;

FIG. 7 shows a format of a PUCCH ACK/NAK payload in which a spreadingfactor of three may be applied to a first group of three symbol periodsand a spreading factor of two may be applied to a second group of twosymbol periods, in accordance with various aspects of the presentdisclosure;

FIG. 8 shows a format of a PUCCH ACK/NAK payload in which a firstspreading factor of two may be applied to a first group of one symbolperiod, a second spreading factor of two may be applied to a secondgroup of two symbol periods, and a third spreading factor of two may beapplied within a third group of two symbol periods, in accordance withvarious aspects of the present disclosure;

FIG. 9 shows a format of a PUCCH ACK/NAK payload in which each spreadingfactor of a plurality of spreading factors of two is applied to arespective groups of one symbol period, in accordance with variousaspects of the present disclosure;

FIG. 10 shows an application of a spreading factor of two to datasymbols (e.g., quadrature phase-shift keying (QPSK) symbols) within asymbol period, using a Walsh code, in accordance with various aspects ofthe present disclosure;

FIG. 11 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 12 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 13 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 14 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 15 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 16 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 17 shows a block diagram of a UE for use in wireless communication,in accordance with various aspects of the present disclosure;

FIG. 18 shows a block diagram of a base station (e.g., a base stationforming part or all of an eNB) for use in wireless communication, inaccordance with various aspects of the present disclosure;

FIG. 19 is a block diagram of a multiple input/multiple output (MIMO)communication system including a base station and a UE, in accordancewith various aspects of the present disclosure;

FIG. 20 is a flow chart illustrating an exemplary method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 21 is a flow chart illustrating an exemplary method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 22 is a flow chart illustrating an exemplary method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 23 is a flow chart illustrating an exemplary method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 24 is a flow chart illustrating an exemplary method for wirelesscommunication, in accordance with various aspects of the presentdisclosure; and

FIG. 25 is a flow chart illustrating an exemplary method for wirelesscommunication, in accordance with various aspects of the presentdisclosure.

DETAILED DESCRIPTION

Techniques are described for increasing the number of downlink componentcarriers that can be acknowledged (ACK'd) or non-acknowledged (NAK'd) ina payload of an uplink control channel, while providing an ability tomultiplex use of the payload between multiple UEs when a single UE doesnot use the entire payload. In the past, the size of an LTE/LTE-A PUCCHACK/NAK payload has been static and has allowed the ACKing or NAKing ofup to five downlink component carriers (CCs). Specific examplesdescribed in the present disclosure enable up to 32 downlink CCs to beACK'd or NAK'd in an LTE/LTE-A PUCCH ACK/NAK payload, and enable theformat of the payload to be selected to optimize its use by multiple UEsor by a UE ACKing or NAKing transmissions over a greater number ofdownlink CCs. The techniques described in the present disclosure mayalso be used to select a PUCCH ACK/NAK payload format for ACKing orNAKing transmissions over any number of downlink CCs.

The following description provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various steps may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in other examples.

FIG. 1 illustrates an example of a wireless communication system 100, inaccordance with various aspects of the disclosure. The wirelesscommunication system 100 may include base stations 105, UEs 115, and acore network 130. The core network 130 may provide user authentication,access authorization, tracking, Internet Protocol (IP) connectivity, andother access, routing, or mobility functions. The base stations 105 mayinterface with the core network 130 through backhaul links 132 (e.g.,S1, etc.) and may perform radio configuration and scheduling forcommunication with the UEs 115, or may operate under the control of abase station controller (not shown). In various examples, the basestations 105 may communicate, either directly or indirectly (e.g.,through core network 130), with each other over backhaul links 134 (e.g.X1, etc.), which may be wired or wireless communication links.

The base stations 105 may wirelessly communicate with the UEs 115 viaone or more base station antennas. Each of the base station 105 sitesmay provide communication coverage for a respective geographic coveragearea 110. In some examples, a base station 105 may be referred to as abase transceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a Home NodeB, a Home eNodeB, orsome other suitable terminology. The geographic coverage area 110 for abase station 105 may be divided into sectors making up a portion of thecoverage area (not shown). The wireless communication system 100 mayinclude base stations 105 of different types (e.g., macro or small cellbase stations). There may be overlapping geographic coverage areas 110for different technologies.

In some examples, the wireless communication system 100 may include anLTE/LTE-A network. In LTE/LTE-A networks, the term evolved Node B (eNB)may be used to describe the base stations 105, while the term UE may beused to describe the UEs 115. The wireless communication system 100 maybe a Heterogeneous LTE/LTE-A network in which different types of eNBsprovide coverage for various geographical regions. For example, each eNBor base station 105 may provide communication coverage for a macro cell,a small cell, or other types of cell. The term “cell” is a 3GPP termthat can be used to describe a base station, a carrier or componentcarrier associated with a base station, or a coverage area (e.g.,sector, etc.) of a carrier or base station, depending on context.

A macro cell may cover a relatively large geographic area (e.g., severalkilometers in radius) and may allow unrestricted access by UEs withservice subscriptions with the network provider. A small cell may be alower-powered base station, as compared with a macro cell that mayoperate in the same or different (e.g., dedicated, shared, etc.) radiofrequency spectrums as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cellmay cover a relatively smaller geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell also may cover a relatively small geographic area(e.g., a home) and may provide restricted access by UEs having anassociation with the femto cell (e.g., UEs in a closed subscriber group(CSG), UEs for users in the home, and the like). An eNB for a macro cellmay be referred to as a macro eNB. An eNB for a small cell may bereferred to as a small cell eNB, a pico eNB, a femto eNB or a home eNB.An eNB may support one or multiple (e.g., two, three, four, and thelike) cells (e.g., component carriers).

The wireless communication system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations mayhave similar frame timing, and transmissions from different basestations may be approximately aligned in time. For asynchronousoperation, the base stations may have different frame timing, andtransmissions from different base stations may not be aligned in time.The techniques described herein may be used for either synchronous orasynchronous operations.

The communication networks that may accommodate some of the variousdisclosed examples may be packet-based networks that operate accordingto a layered protocol stack. In the user plane, communications at thebearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based.A Radio Link Control (RLC) layer may perform packet segmentation andreassembly to communicate over logical channels. A Medium Access Control(MAC) layer may perform priority handling and multiplexing of logicalchannels into transport channels. The MAC layer may also use Hybrid ARQ(HARD) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and the base stations 105 or corenetwork 130 supporting radio bearers for the user plane data. At thephysical (PHY) layer, the transport channels may be mapped to physicalchannels.

The UEs 115 may be dispersed throughout the wireless communicationsystem 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso include or be referred to by those skilled in the art as a mobilestation, a subscriber station, a mobile unit, a subscriber unit, awireless unit, a remote unit, a mobile device, a wireless device, awireless communications device, a remote device, a mobile subscriberstation, an access terminal, a mobile terminal, a wireless terminal, aremote terminal, a handset, a user agent, a mobile client, a client, orsome other suitable terminology. A UE 115 may be a cellular phone, apersonal digital assistant (PDA), a wireless modem, a wirelesscommunication device, a handheld device, a tablet computer, a laptopcomputer, a cordless phone, a wireless local loop (WLL) station, or thelike. A UE may be able to communicate with various types of basestations and network equipment, including macro eNBs, small cell eNBs,relay base stations, and the like.

In some examples, each communication link 125 may include one or morecarriers, where each carrier may be a signal made up of multiplesub-carriers (e.g., waveform signals of different frequencies) modulatedaccording to the various radio technologies described above. Eachmodulated signal may be sent on a different sub-carrier and may carrycontrol information (e.g., reference signals, control channels, etc.),overhead information, user data, etc. The communication links 125 maytransmit bidirectional communications using a frequency domain duplexing(FDD) operation (e.g., using paired spectrum resources) or a time domainduplexing (TDD) operation (e.g., using unpaired spectrum resources).Frame structures for FDD operation (e.g., frame structure type 1) andTDD operation (e.g., frame structure type 2) may be defined.

In some examples of the wireless communication system 100, base stations105 or UEs 115 may include multiple antennas for employing antennadiversity schemes to improve communication quality and reliabilitybetween base stations 105 and UEs 115. Additionally or alternatively,base stations 105 or UEs 115 may employ multiple-input, multiple-output(MIMO) techniques that may take advantage of multi-path environments totransmit multiple spatial layers carrying the same or different codeddata.

The wireless communication system 100 may support operation on multiplecells or carriers, a feature which may be referred to as carrieraggregation (CA) or dual-connectivity operation. A carrier may also bereferred to as a component carrier (CC), a layer, a channel, etc. Theterms “carrier,” “component carrier,” “cell,” and “channel” may be usedinterchangeably herein. A UE 115 may be configured with multipledownlink CCs and one or more uplink CCs for carrier aggregation. Carrieraggregation may be used with both FDD and TDD component carriers. When aUE operates in a CA or dual-connectivity mode of operation, downlinktransmissions received by a UE on a plurality of downlink CCs may beacknowledged individually, on the same or different uplink CCs, or aspart of a PUCCH ACK/NAK payload transmitted on one or more uplink CCs.

In some examples, the wireless communication system 100 may supportoperation over a dedicated radio frequency spectrum (e.g., a radiofrequency spectrum for which transmitting apparatuses may not contendfor access because the radio frequency spectrum is licensed toparticular users for particular uses, such as a licensed radio frequencyspectrum usable for LTE/LTE-A communications) or a shared radiofrequency spectrum (e.g., a radio frequency spectrum for whichtransmitting apparatuses contend for access (e.g., a radio frequencyspectrum that is available for unlicensed use, such as Wi-Fi use, or aradio frequency spectrum that is available for use by multiple operatorsin an equally shared or prioritized manner)). The downlink CCs anduplink CCs allocated to a UE may all be allocated over the dedicatedradio frequency spectrum, all be allocated over the shared radiofrequency spectrum, or be allocated over a combination of the dedicatedradio frequency spectrum and the shared radio frequency spectrum.

The communication links 125 shown in wireless communication system 100may include downlink (DL) transmissions, from a base station 105 to a UE115, or uplink (UL) transmissions, from a UE 115 to a base station 105.The downlink transmissions may also be called forward linktransmissions, while the uplink transmissions may also be called reverselink transmissions. The downlink transmissions may include, for example,a physical downlink shared channel (PDSCH), a physical downlink controlchannel (PDCCH; e.g., for transmission over a dedicated radio frequencyspectrum), or an enhanced PDCCH (EPDCCH; e.g., for transmission over ashared radio frequency spectrum). The uplink transmissions may include,for example, a physical uplink shared channel (PUSCH) or a physicaluplink control channel (PUCCH). In some cases, downlink transmissionsreceived by a UE on a PDSCH may be acknowledged (ACK'd) ornon-acknowledged (NAK'd) by ACK/NAK bits transmitted in an uplinktransmission over a PUCCH.

As the number of CCs used in a carrier aggregation scenario increases,new techniques for transmitting ACK and NAK messages may utilized by theUEs 115 of the wireless communication system 100. In particular, a UE115 may select a PUCCH format to transmit ACK/NAK messages based on thenumber of downlink CCs scheduled for the UE during a reporting interval.For example, the UE may determine a number of ACK/NAK bits to beincluded in a PUCCH payload for the reporting interval based at least inpart on the number of downlink CCs scheduled for the reporting interval.Based on the determined number of bits, the UE 115 may select a PUCCHformat. Examples of PUCCH frame types and techniques for selecting anappropriate PUCCH frame for a given reporting interval are explained inmore detail below.

FIG. 2 shows a wireless communication system 200 in which LTE/LTE-A maybe deployed under different scenarios using a shared radio frequencyspectrum, in accordance with various aspects of the present disclosure.More specifically, FIG. 2 illustrates examples of a supplementaldownlink mode (also referred to as a licensed assisted access mode), acarrier aggregation mode, and a standalone mode in which LTE/LTE-A isdeployed using a shared radio frequency spectrum. The wirelesscommunication system 200 may be an example of portions of the wirelesscommunication system 100 described with reference to FIG. 1. Moreover, afirst base station 205 and a second base station 205-a may be examplesof aspects of one or more of the base stations 105 described withreference to FIG. 1, while a first UE 215, a second UE 215-a, a third UE215-b, and a fourth UE 215-c may be examples of aspects of one or moreof the UEs 115 described with reference to FIG. 1.

In the example of a supplemental downlink mode (e.g., a licensedassisted access mode) in the wireless communication system 200, thefirst base station 205 may transmit OFDMA waveforms to the first UE 215using a downlink channel 220. The downlink channel 220 may be associatedwith a frequency F1 in a shared radio frequency spectrum. The first basestation 205 may transmit OFDMA waveforms to the first UE 215 using afirst bidirectional link 225 and may receive SC-FDMA waveforms from thefirst UE 215 using the first bidirectional link 225. The firstbidirectional link 225 may be associated with a frequency F4 in adedicated radio frequency spectrum. The downlink channel 220 in theshared radio frequency spectrum and the first bidirectional link 225 inthe dedicated radio frequency spectrum may operate contemporaneously.The downlink channel 220 may provide a downlink capacity offload for thefirst base station 205. In some examples, the downlink channel 220 maybe used for unicast services (e.g., addressed to one UE) or formulticast services (e.g., addressed to several UEs). This scenario mayoccur with any service provider (e.g., a mobile network operator (MNO))that uses a dedicated radio frequency spectrum and desires to relievesome of the traffic or signaling congestion.

In one example of a carrier aggregation mode in the wirelesscommunication system 200, the first base station 205 may transmit OFDMAwaveforms to the second UE 215-a using a second bidirectional link 230and may receive OFDMA waveforms, SC-FDMA waveforms, or resource blockinterleaved FDMA waveforms from the second UE 215-a using the secondbidirectional link 230. The second bidirectional link 230 may beassociated with the frequency F1 in the shared radio frequency spectrum.The first base station 205 may also transmit OFDMA waveforms to thesecond UE 215-a using a third bidirectional link 235 and may receiveSC-FDMA waveforms from the second UE 215-a using the third bidirectionallink 235. The third bidirectional link 235 may be associated with afrequency F2 in a dedicated radio frequency spectrum. The secondbidirectional link 230 may provide a downlink and uplink capacityoffload for the first base station 205. Like the supplemental downlink(e.g., the licensed assisted access mode) described above, this scenariomay occur with any service provider (e.g., MNO) that uses a dedicatedradio frequency spectrum and desires to relieve some of the traffic orsignaling congestion.

In another example of a carrier aggregation mode in the wirelesscommunication system 200, the first base station 205 may transmit OFDMAwaveforms to the third UE 215-b using a fourth bidirectional link 240and may receive OFDMA waveforms, SC-FDMA waveforms, or resource blockinterleaved waveforms from the third UE 215-b using the fourthbidirectional link 240. The fourth bidirectional link 240 may beassociated with a frequency F3 in the shared radio frequency spectrum.The first base station 205 may also transmit OFDMA waveforms to thethird UE 215-b using a fifth bidirectional link 245 and may receiveSC-FDMA waveforms from the third UE 215-b using the fifth bidirectionallink 245. The fifth bidirectional link 245 may be associated with thefrequency F2 in the dedicated radio frequency spectrum. The fourthbidirectional link 240 may provide a downlink and uplink capacityoffload for the first base station 205. This example and those providedabove are presented for illustrative purposes and there may be othersimilar modes of operation or deployment scenarios that combineLTE/LTE-A in a dedicated radio frequency spectrum and use a shared radiofrequency spectrum for capacity offload.

As described above, one type of service provider that may benefit fromthe capacity offload offered by using LTE/LTE-A in a shared radiofrequency spectrum is a traditional MNO having access rights to anLTE/LTE-A dedicated radio frequency spectrum. For these serviceproviders, an operational example may include a bootstrapped mode (e.g.,supplemental downlink (e.g., licensed assisted access), carrieraggregation) that uses the LTE/LTE-A primary component carrier (PCC) onthe dedicated radio frequency spectrum and at least one secondarycomponent carrier (SCC) on the shared radio frequency spectrum.

In the carrier aggregation mode, data and control may, for example, becommunicated in the dedicated radio frequency spectrum (e.g., via firstbidirectional link 225, third bidirectional link 235, and fifthbidirectional link 245) while data may, for example, be communicated inthe shared radio frequency spectrum (e.g., via second bidirectional link230 and fourth bidirectional link 240). The carrier aggregationmechanisms supported when using a shared radio frequency spectrum mayfall under a hybrid frequency division duplexing-time division duplexing(FDD-TDD) carrier aggregation or a TDD-TDD carrier aggregation withdifferent symmetry across component carriers.

In one example of a standalone mode in the wireless communication system200, the second base station 205-a may transmit OFDMA waveforms to thefourth UE 215-c using a bidirectional link 250 and may receive OFDMAwaveforms, SC-FDMA waveforms, or resource block interleaved FDMAwaveforms from the fourth UE 215-c using the bidirectional link 250. Thebidirectional link 250 may be associated with the frequency F3 in theshared radio frequency spectrum. The standalone mode may be used innon-traditional wireless access scenarios, such as in-stadium access(e.g., unicast, multicast). An example of a type of service provider forthis mode of operation may be a stadium owner, cable company, eventhost, hotel, enterprise, or large corporation that does not have accessto a dedicated radio frequency spectrum.

In some examples, a transmitting apparatus such as one of the basestations 105, 205, or 205-a described with reference to FIG. 1 or 2, orone of the UEs 115, 215, 215-a, 215-b, or 215-c described with referenceto FIG. 1 or 2, may use a gating interval to gain access to a channel ofa shared radio frequency spectrum (e.g., to a physical channel of theshared radio frequency spectrum). In some examples, the gating intervalmay be periodic. For example, the periodic gating interval may besynchronized with at least one boundary of an LTE/LTE-A radio interval.The gating interval may define the application of a contention-basedprotocol, such as an LBT protocol based on the LBT protocol specified inEuropean Telecommunications Standards Institute (ETSI) (EN 301 893).When using a gating interval that defines the application of an LBTprotocol, the gating interval may indicate when a transmitting apparatusis to perform a contention procedure (e.g., an LBT procedure) such as aclear channel assessment (CCA) procedure. The outcome of the CCAprocedure may indicate to the transmitting apparatus whether a channelof a shared radio frequency spectrum is available or in use for thegating interval (also referred to as an LBT radio frame). When a CCAprocedure indicates that the channel is available for a correspondingLBT radio frame (e.g., “clear” for use), the transmitting apparatus mayreserve or use the channel of the shared radio frequency spectrum duringpart or all of the LBT radio frame. When the CCA procedure indicatesthat the channel is not available (e.g., that the channel is in use orreserved by another transmitting apparatus), the transmitting apparatusmay be prevented from using the channel during the LBT radio frame.

FIG. 3 shows a wireless communication system 300 in which LTE/LTE-A maybe deployed in a carrier aggregation scenario, in accordance withvarious aspects of the present disclosure. The wireless communicationsystem 300 may be an example of portions of the wireless communicationsystem 100 or 200 described with reference to FIG. 1 or 2. Moreover, abase station 305 may be an example of aspects of one or more of the basestations 105, 205, or 205-a described with reference to FIG. 1 or 2,while a UE 315 may be an examples of aspects of one or more of the UEs115, 215, 215-a, 215-b, or 215-c described with reference to FIG. 1 or2.

When communicating in a carrier aggregation mode using LTE/LTE-Acommunications, the UE 315 has traditionally communicated with the basestation 305 using up to five component carriers. However, techniquesdescribed in the present disclosure can increase the size of a PUCCHACK/NAK payload to allow communication over up to 32 component carriers.One of the component carriers may be designated as a primary componentcarrier, and the remaining component carriers may be designated assecondary component carriers. Each component carrier may be configuredas a downlink component carrier, an uplink component carrier, or a cell(e.g., a component carrier that may be configured for use as a downlinkcomponent carrier and/or an uplink component carrier). By way ofexample, FIG. 3 illustrates communication between the UE 315 and thebase station 305 over five component carriers, including a firstdownlink component carrier 320, a second downlink component carrier 325,a third downlink component carrier 330, a first uplink component carrier335, and a second uplink component carrier 340. Each of the firstdownlink component carrier 320, the second downlink component carrier325, the third downlink component carrier 330, the first uplinkcomponent carrier 335, and the second uplink component carrier 340 mayoperate in a dedicated radio frequency spectrum or a shared radiofrequency spectrum, depending on how the component carrier is allocatedor configured.

When the UE 315 is configured for operation in a supplemental downlinkmode of operation using a shared radio frequency spectrum, as describedwith reference to FIG. 2, and when the UE 315 is operating in a carrieraggregation mode, one or more of the first downlink component carrier320, the second downlink component carrier 325, and the third downlinkcomponent carrier 330 may operate in the licensed radio frequencyspectrum band; one or more of the first downlink component carrier 320,the second downlink component carrier 325, and the third downlinkcomponent carrier 330 may operate in the shared radio frequencyspectrum; and the first uplink component carrier 335 and the seconduplink component carrier 340 may operate in the dedicated radiofrequency spectrum.

When the UE 315 is configured for operation in a carrier aggregationmode of operation using the shared radio frequency spectrum, asdescribed with reference to FIG. 2, one or more of the first downlinkcomponent carrier 320, the second downlink component carrier 325, andthe third downlink component carrier 330 may operate in the dedicatedradio frequency spectrum; one or more of the first downlink componentcarrier 320, the second downlink component carrier 325, and the thirddownlink component carrier 330 may operate in the shared radio frequencyspectrum; one or more of the first uplink component carrier 335 and thesecond uplink component carrier 340 may operate in the dedicated radiofrequency spectrum band; and one or more of the first uplink componentcarrier 335 and the second uplink component carrier 340 may operate inthe shared radio frequency spectrum. In some examples, all of thedownlink component carriers may operate in the dedicated radio frequencyspectrum, or all of the uplink component carriers may operate in theshared radio frequency spectrum, but not all of the downlink componentcarriers and all of the uplink component carriers may operate in theshared radio frequency spectrum (e.g., at least one downlink componentcarrier or at least one uplink component carrier operates in thededicated radio frequency spectrum).

When the UE 315 is configured for operation in a standalone mode ofoperation using the shared radio frequency spectrum, as described withreference to FIG. 2, and when the UE 315 is operating in a carrieraggregation mode, all of the first downlink component carrier 320, thesecond downlink component carrier 325, the third downlink componentcarrier 330, the first uplink component carrier 335, and the seconduplink component carrier 340 may operate in the shared radio frequencyspectrum.

FIG. 4 shows an exemplary resource block (RB) of a PUCCH, which RB maybe transmitted or received during a subframe 400, in accordance withvarious aspects of the present disclosure. In some examples, the RB maybe transmitted by one or more of the UEs 115, 215, 215-a, 215-b, 215-c,or 315 described with reference to FIG. 1, 2, or 3, or transmitted byone or more of the base stations 105, 205, 205-a, or 305 described withreference to FIG. 1, 2, or 3. The subframe 400 includes a first slot 405(e.g., Slot 0) and a second slot 410 (e.g., Slot 1), with each slotbeing configured for operation in an LTE/LTE-A normal cyclic prefix (CP)mode and including seven symbol periods numbered 0, 1, 2, 3, 4, 5, and6. Demodulation reference signals (DM-RSs) may be transmitted in thesubframe in accordance with an LTE/LTE-A PUCCH Format 3 for normal CP(e.g., during symbol periods 1 and 5 of each slot of the subframe). Thepresent disclosure describes how a slot of the subframe 400 may beformatted for the transmission or reception of PUCCH ACK/NAK payloads ofvarying size.

FIG. 5 shows an exemplary RB of a PUCCH, which RB may be transmitted orreceived during a subframe 500, in accordance with various aspects ofthe present disclosure. In some examples, the RB may be transmitted byone or more of the UEs 115, 215, 215-a, 215-b, 215-c, or 315 describedwith reference to FIG. 1, 2, or 3, or transmitted by one or more of thebase stations 105, 205, 205-a, or 305 described with reference to FIG.1, 2, or 3. The subframe 500 includes a first slot 505 (e.g., Slot 0)and a second slot 510 (e.g., Slot 1), with each slot being configuredfor operation in an LTE/LTE-A extended CP mode and including six symbolperiods numbered 0, 1, 2, 3, 4, and 5. Demodulation reference signals(DM-RSs) may be transmitted in the subframe in accordance with anLTE/LTE-A PUCCH Format 3 for extended CP (e.g., during symbol period 3of each slot of the subframe). The present disclosure describes how aslot of the subframe 500 may be formatted for the transmission orreception of PUCCH ACK/NAK payloads of varying size.

FIGS. 6-10 describe various PHY layer designs for a PUCCH. Moreparticularly, FIG. 6 shows an exemplary table 600 of predeterminedformats of a PUCCH ACK/NAK payload, from which a format of a PUCCHACK/NAK payload may be selected by a UE or base station, for a reportinginterval, in accordance with various aspects of the present disclosure.At a UE such as one of the UEs 115, 215, 215-a, 215-b, 215-c, or 315described with reference to FIG. 1, 2, or 3, the UE may select one ofthe formats for transmitting a PUCCH ACK/NAK payload for a reportinginterval. At a base station such as one of the base stations 105, 205,205-a, or 305 described with reference to FIG. 1, 2, or 3, the basestation may select one of the formats for decoding the PUCCH ACK/NAKpayload.

By way of example, FIG. 6 shows five exemplary formats of a PUCCHACK/NAK payload, from which a UE or base station may select a format,for a reporting interval, based at least in part on a number of bits tobe included in a PUCCH ACK/NAK payload for the reporting interval. Thenumber of bits to be included in the PUCCH ACK/NAK payload may bedetermined based at least in part on a number of downlink CCs scheduledfor the UE during the reporting interval. By way of example, thepredefined formats for the PUCCH ACK/NAK payload may include differentcombinations of: UE multiplexing densities within a RB, spreadingfactors, or numbers of RBs allocated per symbol period.

A first format 605 of the PUCCH ACK/NAK payload may include a UEmultiplexing density, within a RB, of at least four UEs (e.g., four orfive UEs). In some examples, the first format may employ a DualReed-Muller (Dual RM) coding of its payload. The first format may beselected, for example, when the number of bits to be included in anACK/NAK payload is 21 or fewer bits (or from 1 to 21 bits) and a RB isconfigured as described with reference to FIG. 4 or 5.

A second format 610 of the PUCCH ACK/NAK payload may include a UEmultiplexing density, within a RB, of two UEs. The second format mayalso include at least two groups of symbol periods, where each of the atleast two groups of symbol periods includes at least one symbol, andwhere spreading is applied independently within each of the at least twogroups of symbol periods. In some examples, the second format may encodeits payload using Tail-Biting Convolutional Coding (TBCC). The secondformat may be selected, for example, when the number of bits to beincluded in the ACK/NAK payload is 60 or fewer bits (or from 22 to 60bits) and a RB is configured as described with reference to FIG. 4 or 5.

A third format 615 of the PUCCH ACK/NAK payload may include no UEmultiplexing within a RB, no spreading factor, and an RB allocation persymbol period of one. In some examples, the third format may encode itspayload using TBCC or Turbo coding. The third format may be selected,for example, when the number of bits to be included in the ACK/NAKpayload is 120 or fewer bits (or from 61 to 120 bits) and a RB isconfigured as described with reference to FIG. 4 or 5.

A fourth format 620 of the PUCCH ACK/NAK payload may include no UEmultiplexing within a RB, no spreading factor, and an RB allocation persymbol period of two. In some examples, the fourth format may encode itspayload using TBCC or Turbo coding. The fourth format may be selected,for example, when the number of bits to be included in the ACK/NAKpayload is 240 or fewer bits (or from 121 to 240 bits) and a RB isconfigured as described with reference to FIG. 4 or 5.

A fifth format 625 of the PUCCH ACK/NAK payload may include no UEmultiplexing within a RB, no spreading factor, and an RB allocation persymbol period of three. In some examples, the fifth format may encodeits payload using TBCC or Turbo coding. The fifth format may beselected, for example, when the number of bits to be included in theACK/NAK payload is 360 or fewer bits (or from 241 to 360 bits) and a RBis configured as described with reference to FIG. 4 or 5.

Each format of a PUCCH ACK/NAK payload shown in FIG. 6 may have anLTE/LTE-A PUCCH Format 3 reference signal symbol structure. That is, forexample, when a PUCCH ACK/NAK payload is transmitted using a normalcyclic prefix (CP), the format of the PUCCH ACK/NAK payload may have tworeference signal symbol periods per slot of a subframe; and when a PUCCHACK/NAK payload is transmitted using an extended CP, the format of thePUCCH ACK/NAK payload may have one reference signal symbol per slot of asubframe. In some examples, the reference signals transmitted in thereference signal symbol periods may include demodulation referencesignals (DM-RSs).

Each format of a PUCCH ACK/NAK payload that has no spreading factor(e.g., the third format 615, the fourth format 620, and the fifth format625) may have a data structure similar to that of a PUSCH. Processing ofa PUCCH ACK/NAK payload transmitted using one of the third format 615,the fourth format 620, or the fifth format 625 may therefore be similarto the processing of an LTE/LTE-A PUSCH.

FIGS. 7-9 illustrate various examples of the second format 610 of aPUCCH ACK/NAK payload shown in FIG. 6. More particularly, FIG. 7 shows aformat 700 of a PUCCH ACK/NAK payload in which a spreading factor ofthree (SF3) may be applied to a first group 710 of three symbol periodsand a spreading factor of two (SF2) may be applied to a second group 715of two symbol periods, in accordance with various aspects of the presentdisclosure. By way of example, the groups of symbol periods are shown tobe symbol periods in a slot 705 of a subframe transmitted using a normalCP. In another example, the first group of three symbol periods and thesecond group of two symbol periods could be groups of symbol periods ina slot of a subframe transmitted using an extended CP.

In FIG. 7, the first group 710 of three symbol periods is shown toinclude symbol periods 0, 2, and 3, and the second group 715 of twosymbol periods is shown to include symbol periods 4 and 6. Whenmultiplexing the transmission of PUCCH ACK/NAK payloads for two UEs inthe slot, two of three orthogonal cover codes (OCCs) may be used whenapplying the spreading factor of three to the symbol periods 0, 2, and3. This reduces the maximum PUCCH ACK/NAK payload for a UE from 60 bitsto 48 bits, and may result in an unequal signal-to-noise-ratio (SNR)across the coded bits of the first group 710 of three symbol periodscompared to the coded bits of the second group 715 of two symbolperiods.

FIG. 8 shows a format 800 of a PUCCH ACK/NAK payload in which a firstspreading factor of two (SF2) may be applied to a first group 810 of onesymbol period, a second spreading factor of two (SF2) may be applied toa second group 815 of two symbol periods, and a third spreading factorof two (SF2) may be applied within a third group 820 of two symbolperiods, in accordance with various aspects of the present disclosure.By way of example, the groups of symbol periods are shown to be symbolperiods in a slot 805 of a subframe transmitted using a normal CP. Inanother example, the groups could be groups of symbol periods in a slotof a subframe transmitted using an extended CP.

In FIG. 8, the first group 810 of one symbol period is shown to includesymbol period 0, the second group 815 of two symbol periods is shown toinclude symbol periods 2 and 3, and the third group 820 of two symbolperiods is shown to include symbol periods 4 and 6. The first spreadingfactor may be applied using a Walsh code (e.g., a block of six datasymbols may be repeated once and a Walsh code W2 (e.g., [++ for a firstUE, and +− for a second UE]) may be used on the repetitions forspreading before applying a Discrete Fourier Transform (DFT) to the datasymbols) or using elements of an orthogonal Fast Fourier Transform (FFT)matrix (e.g., a block of six data symbols may be repeated once and acode of [1, 1, . . . , 1; 1,

$\left\lbrack {1,1,\ldots \mspace{14mu},{1;1},\left. e\uparrow\frac{2\; \pi \; i}{12} \right.,{\left. e\uparrow 2 \right.*\frac{2\; \pi \; i}{12}},\ldots \mspace{14mu},{\left. e\uparrow 11 \right.*\frac{2\; \pi \; i}{12}}} \right\rbrack$

. . . ,may be used on the repetitions for spreading before applying a DFT tothe data symbols). A more detailed illustration of applying a spreadingfactor of two to a symbol period using a Walsh code is described withreference to FIG. 10.

FIG. 9 shows a format 900 of a PUCCH ACK/NAK payload in which eachspreading factor (SF2) of a plurality of spreading factors of two isapplied to a respective groups 910, 915, 920, 925, and 930 of one symbolperiod, in accordance with various aspects of the present disclosure. Byway of example, the groups of symbol periods are shown to be symbolperiods in a slot of a subframe transmitted using a normal CP. Inanother example, the first group of three symbol periods and the secondgroup of two symbol periods could be groups of symbol periods in a slot905 of a subframe transmitted using an extended CP.

In FIG. 9, each spreading factor of two may be applied using a Walshcode (e.g., a block of six data symbols may be repeated once and a Walshcode W2 (e.g., [++ for a first UE, and +− for a second UE]) may be usedon the repetitions for spreading before applying a DFT to the datasymbols) or using elements of an orthogonal FFT matrix (e.g., a block ofsix data symbols may be repeated once and a code of [1, 1, . . . , 1; 1,

$\left\lbrack {1,1,\ldots \mspace{14mu},{1;1},\left. e\uparrow\frac{2\; \pi \; i}{12} \right.,{\left. e\uparrow 2 \right.*\frac{2\; \pi \; i}{12}},\ldots \mspace{14mu},{\left. e\uparrow 11 \right.*\frac{2\; \pi \; i}{12}}} \right\rbrack$

. . . ,may be used on the repetitions for spreading before applying a DFT tothe data symbols). A more detailed illustration of applying a spreadingfactor of two to a symbol period using a Walsh code is described withreference to FIG. 10.

FIG. 10 shows an application of a spreading factor of two to datasymbols (e.g., quadrature phase-shift keying (QPSK) symbols) within asymbol period, using a Walsh code, in accordance with various aspects ofthe present disclosure. The application shown may be used, for example,to apply the spreading factor of two to the first group of one symbolperiod described with reference to FIG. 8 or, individually, to any ofthe groups of one symbol period described with reference to FIG. 9.

As shown in FIG. 10, a block 1005 of six data symbols (e.g., QPSKsymbols x₀, x₁, x₂, x₃, x₄, x₅) may be repeated once (as block 1010) anda Walsh code W2 (e.g., [++ for a first UE, and +− for a second UE]) maybe used on the repetitions for spreading before applying a DFT 1015 tothe data symbols). Tone mapping may then be performed using an InverseFFT (IFFT) 1020.

With reference to the first format 605 of a PUCCH ACK/NAK payload,described with reference to FIG. 6, orthogonal resources may beallocated for each antenna port of a UE. With reference to the secondformat 610, third format 615, fourth format 620, or fifth format 625 ofa PUCCH ACK/NAK payload, described with reference to FIG. 6, 7, 8, or 9,a space-time block code (STBC) may be used for transmission diversity(TxDiv). Use of an SBTC involves no special handling for symbol periodgroups of one symbol period. When using SBTC, and in some examples, fourorthogonal DM-RS resources may be allocated for the second format 610 ofa PUCCH ACK/NAK payload, and two orthogonal DM-RS resources may beallocated for the third format 615, fourth format 620, or fifth format625 of a PUCCH ACK/NAK payload.

As an example of using SBTC, assume that without TxDiv, the transmittedSC-FDM data symbols would be [Y₀, Y₁, Y₂, Y₃, Y₄] (ignoring DM-RS symbolperiods). With TxDiv using SBTC, the transmitted SC-FDM data symbols maybe, for example, [Y₀, Y₁*, Y₂, Y₃*, Y₄] for Antenna port 0, and [Y₁,−Y₀*, Y₃, −Y₂*, Y₄] for Antenna port 1.

The PHY layer designs for a PUCCH described in FIGS. 6-10, and elsewherein the present disclosure, may be extended to PUCCH higher ordermodulation (e.g., 16 quadrature amplitude modulation (QAM)) or MIMO. Ina MIMO context, multiple DM-RS resources per UE may be appropriate(e.g., similar to what was described above in the context of TxDiv).Higher order modulation and MIMO can increase the supportable PUCCHACK/NAK payload without reducing UE multiplexing density.

In some examples, the downlink CCs allocated to a UE may be grouped intotwo or more subsets for the purpose of feedback reporting (e.g., for thepurpose of ACK/NAK reporting). A number of bits to be included in aPUCCH ACK/NAK, payload for each group of downlink CCs may then bedetermined for a reporting interval, based at least in part on thenumber of downlink CCs in scheduled for the UE during the reportinginterval; and based at least in part on the determined number of bitsfor each subset, a format of a PUCCH ACK/NAK payload for the subset maybe selected. In some examples, the format of each PUCCH ACK/NAK payloadmay be selected from a set of predefined formats such as the set offormats described with reference to FIG. 6. A separate set of resourcesmay be allocated for each PUCCH ACK/NAK payload.

In some examples, a first PUCCH ACK/NAK payload for a first group ofdownlink CCs may be transmitted on a first uplink CC, and an additionalPUCCH ACK/NAK payload (e.g., a second ACK/NAK payload) for an additionalgroup of downlink CCs (e.g., a second group of downlink CCs) may betransmitted on a second uplink CC. Alternatively, the first PUCCHACK/NAK payload and the additional PUCCH ACK/NAK payload (e.g., thesecond ACK/NAK payload) may be transmitted on a same uplink CC. Whendifferent uplink CCs are used to transmit different PUCCH ACK/NAKpayloads, the PUCCH design may be similar to that of a PUCCH transmittedon a secondary cell (SCell) in a dual connectivity scenario (butpossibly with more than two groups of downlink CCs). When the sameuplink CC is used to transmit different PUCCH ACK/NAK payloads, thePUCCH ACK/NAK payloads may be transmitted using a non-SC-FDM waveform.In some examples, the transmission of different PUCCH ACK/NAK payloadson the same uplink CC may be supported for formats of PUCCH ACK/NAKpayload limited to one RB (e.g., the first format 605, the second format610, and the third format 615 described with reference to FIG. 6).

In some examples, downlink assignment indices (DAIs) may be used for bitmapping and resource selection within a PUCCH ACK/NAK payload. Forexample, a DAI may be associated (e.g., transmitted) with each of anumber of downlink grants transmitted to a UE. The downlink grants mayindicate the downlink CCs scheduled for a UE, and the DAI for a downlinkgrant may indicate a bit mapping and resource selection, in a PUCCHACK/NAK payload, for acknowledging/non-acknowledging each transmissionover each downlink CC scheduled in the downlink grant. In the case ofself-scheduling (i.e., same-CC scheduling), each downlink CC may beassociated with a unique DAI. In the case of cross-CC scheduling, a DAIper grant may apply to multiple downlink CCs, and a DAI for each of themultiple downlink CCs may be implicitly derived. In some examples, a DAImay indicate a bit location across CCs and subframes. In anotherexample, a DAI for a downlink grant may include a sequence numberindicating a relationship between at least one downlink CC scheduled inthe downlink grant and at least one downlink CC scheduled in anotherdownlink grant. In these examples, a bit mapping and resource selectionfor acknowledging/non-acknowledging a downlink CC (or downlink CCs) in aPUCCH ACK/NAK payload may be determined based at least in part on thesequence number. In some examples, the sequence number may be a numbergenerated by an n-bit counter, where n is incremented across CCs firstand subframes second, with a cyclic wrap-around.

Bit mapping may directly follow DAI processing when the DAI is anabsolute ACK/NAK bit location indicator. Bit mapping may follow DAIprocessing, including unwrapping, when the DAI includes a sequencenumber.

When a DAI includes a sequence number, the set of sequence numbersreceived by a UE for a reporting interval may be used to determine thetotal number of downlink CCs, N, that are scheduled for the UE in thereporting interval. In the case of MIMO use, a UE may select thesmallest PUCCH ACK/NAK payload format that supports 2N bits. In someexamples, RRC-configured bundling for sets of downlink CCs or subframesmay be factored into the Nor 2N numbers. The omission of feedback forsome downlink CCs may also be factored into the Nor 2N numbers.

In some cases, a UE may not receive or properly decode one or moredownlink grants. When a non-received or improperly decoded downlinkgrant is transmitted to the UE before another downlink grant, whichother downlink grant is received by the UE and associated with asequence number following the sequence number of the non-received orimproperly decoded downlink grant, the UE may use the sequence number(s)it receives to determine how many downlink grants it should havereceived and, in some cases, select the correct PUCCH ACK/NAK payloadformat based on a determination of the number of bits that the UE issupposed to acknowledge/non-acknowledge in the PUCCH ACK/NAK payload.However, when a non-received or improperly decoded downlink grant istransmitted to the UE after all other downlink grants, the UE may selectan incorrect PUCCH ACK/NAK payload format that supports a smaller sizepayload (e.g., based on the UE's determination of a smaller value for Nor 2N). To mitigate such an incorrect determination, and the ambiguitythat might result from selecting an unexpected PUCCH ACK/NAK payloadformat, a base station may introduce sequence discontinuities into thesequence numbers associated with a plurality of DAIs. The sequencediscontinuities may serve to pad the sequence numbers, such that a UEwill be caused to determine a value of N or 2N that is large enough tocause selection of the appropriate PUCCH ACK/NAK format—even when one ormore last-transmitted downlink grants are not received and the UEtherefore determines an incorrect value of N or 2N. For example, in theabsence of introducing sequence number discontinuities, a base stationmay associate DAI values (before modulo operation) of [0, 2, 4, 6, 8,10, 12, 14, 16, 18, 20] with 11 separate MIMO downlink grantstransmitted to a UE. If the UE receives all but the last downlink grant,the UE may determine N=10 and incorrectly select the first format 105described with reference to FIG. 1. However, if the base stationassociates DAI values (before module operation) of [0, 2, 6, 8, 10, 12,16, 18, 20, 22, 24] with the 11 separate MIMO downlink grants, the UEwould determine N=11 and correctly select the second format 110described with reference to FIG. 1 (even though the correct value of Nwas N=12).

When introducing sequence discontinuities into (or padding) a set ofsequence numbers, a base station knows where the sequencediscontinuities are introduced, and thus can expect NAKs for the PUCCHACK/NAK payload bit positions corresponding to the sequencediscontinuities. Given this expectation, the base station can use theintroduced sequence discontinuities as a virtual cyclic redundancy check(CRC). A base station may also introduce additional sequencediscontinuities for the purpose of increasing the length of the CRC.

In some examples, a base station may associate an ACK/NAK ResourceIndicator (ARI) with each downlink grant transmitted to a UE. In someexamples, each ARI may be a 4-bit value indicating which of sixteendifferent PUCCH resources are to be used for ACK/NAK reporting. In somecases, the different PUCCH resources may be associated with differentuplink CCs (e.g., 10 PUCCH resources may be configured on an uplink CC1and PUCCH resources may be configured on an uplink CC2). Each of thePUCCH resources may be configured (or may be expected to be configured)using the same PUCCH ACK/NAK format.

In some examples, an ARI may have a variable length, so that the lengthof the ARI may be tailored to the number of downlink CCs that arescheduled for a UE during a reporting interval. For example, when a UEis scheduled on 8 downlink CCs with 8 downlink grants, each of the firstfour downlink grants may be associated with an ARI value of a, and eachof the second four downlink grants may be associated with an ARI valueof b. Upon the UE detecting the change in ARI value, the UE mayconcatenate the ARI values in order of CC identity (CC_ID) to derive the8-bit value ab. Unless the UE fails to receive four consecutive downlinkgrants, the appropriate PUCCH resource will be used.

FIG. 11 shows a block diagram 1100 of an apparatus 1115 for use inwireless communication, in accordance with various aspects of thepresent disclosure. The apparatus 1115 may be an example of aspects ofone or more of the UEs 115, 215, 215-a, 215-b, 215-c, or 315 describedwith reference to FIG. 1, 2, or 3, or aspects of one or more of the basestations 105, 205, 205-a, or 305 described with reference to FIG. 1, 2,or 3. The apparatus 1115 may also be or include a processor. Theapparatus 1115 may include a receiver module 1110, a wirelesscommunication management module 1120, or a transmitter module 1130. Eachof these modules may be in communication with each other.

The modules of the apparatus 1115 may, individually or collectively, beimplemented using one or more application-specific integrated circuits(ASICs) adapted to perform some or all of the applicable functions inhardware. Alternatively, the functions may be performed by one or moreother processing units (or cores), on one or more integrated circuits.In other examples, other types of integrated circuits may be used (e.g.,Structured/Platform ASICs, Field Programmable Gate Arrays (FPGAs), andother Semi-Custom ICs), which may be programmed in any manner known inthe art. The functions of each module may also be implemented, in wholeor in part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver module 1110 may include at least oneradio frequency (RF) receiver, such as at least one RF receiver operableto receive transmissions over a dedicated radio frequency spectrum or ashared radio frequency spectrum. The dedicated radio frequency spectrummay include a radio frequency spectrum for which transmittingapparatuses may not contend for access (e.g., a radio frequency spectrumlicensed to particular users for particular uses, such as a licensedradio frequency spectrum usable for LTE/LTE-A communications). Theshared radio frequency spectrum may include a radio frequency spectrumfor which transmitting apparatuses contend for access (e.g., a radiofrequency spectrum that is available for unlicensed use, such as Wi-Fiuse, or a radio frequency spectrum that is available for use by multipleoperators in an equally shared or prioritized manner). In some examples,the dedicated radio frequency spectrum or the shared radio frequencyspectrum may be used for LTE/LTE-A communications, as described, forexample, with reference to FIG. 1, 2, or 3. The receiver module 1110 maybe used to receive various types of data or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system, such as one or more communication links of thewireless communication system 100, 200, or 300 described with referenceto FIG. 1, 2, or 3. The communication links may be established over thededicated radio frequency spectrum or the shared radio frequencyspectrum.

In some examples, the transmitter module 1130 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum or the shared radiofrequency spectrum. The transmitter module 1130 may be used to transmitvarious types of data or control signals (i.e., transmissions) over oneor more communication links of a wireless communication system, such asone or more communication links of the wireless communication system100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the dedicated radiofrequency spectrum or the shared radio frequency spectrum.

In some examples, the wireless communication management module 1120 maybe used to manage one or more aspects of wireless communication for theapparatus 1115. In some examples, the wireless communication managementmodule 1120 may include an ACK/NAK payload size determination module1135 or an ACK/NAK payload format selection module 1140.

In some examples, the ACK/NAK payload size determination module 1135 maybe used to determine, based at least in part on a number of downlink CCsscheduled for a UE during a reporting interval, a number of bits to beincluded in a PUCCH ACK/NAK payload for the reporting interval.

In some examples, the ACK/NAK payload format selection module 1140 maybe used to select, based at least in part on the determined number ofbits, a format of the PUCCH ACK/NAK payload.

In some examples of the apparatus 1115, the ACK/NAK payload formatselection module 1140 may select the format of the PUCCH ACK/NAK payloadby selecting one of a plurality of predefined formats for the PUCCHACK/NAK payload. The predefined formats for the PUCCH ACK/NAK payloadmay include, for example, different combinations of: UE multiplexingdensities within a RB, spreading factors, or numbers of RBs allocatedper symbol period. In some examples, each of the predefined formats forthe PUCCH ACK/NAK payload may be based at least in part on a formatincluding two reference signal symbol periods per slot (e.g., when thepredefined formats are configured for transmissions, in a slot of asubframe, with a normal CP). In some examples, each of the predefinedformats for the PUCCH ACK/NAK payload may be based at least in part on aformat including one reference signal symbol period per slot (e.g., whenthe predefined formats are configured for transmissions, in a slot of asubframe, with an extended CP).

In examples in which the apparatus 1115 is included in a UE, thewireless communication management module 1120 may receive a number ofdownlink grants indicating the downlink CCs scheduled for the UE. Inthese examples, the ACK/NAK payload format selection module 1140 mayselect a PUCCH ACK/NAK payload format for transmitting the PUCCH ACK/NAKpayload.

In examples in which the apparatus 1115 is included in a base station,the wireless communication management module 1120 may transmit, to a UE,a plurality of downlink grants indicating the downlink CCs scheduled forthe UE. In these examples, the ACK/NAK payload format selection module1140 may select a PUCCH ACK/NAK payload format for decoding the PUCCHACK/NAK payload.

FIG. 12 shows a block diagram 1200 of an apparatus 1215 for use inwireless communication, in accordance with various aspects of thepresent disclosure. The apparatus 1215 may be an example of aspects ofone or more of the UEs 115, 215, 215-a, 215-b, 215-c, or 315 describedwith reference to FIG. 1, 2, or 3, aspects of one or more of the basestations 105, 205, 205-a, or 305 described with reference to FIG. 1, 2,or 3, or aspects of the apparatus 1115 described with reference to FIG.11. The apparatus 1215 may also be or include a processor. The apparatus1215 may include a receiver module 1210, a wireless communicationmanagement module 1220, or a transmitter module 1230. Each of thesemodules may be in communication with each other.

The modules of the apparatus 1215 may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each module may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver module 1210 may include at least one RFreceiver, such as at least one RF receiver operable to receivetransmissions over a dedicated radio frequency spectrum or a sharedradio frequency spectrum. The dedicated radio frequency spectrum mayinclude a radio frequency spectrum for which transmitting apparatusesmay not contend for access (e.g., a radio frequency spectrum licensed toparticular users for particular uses, such as a licensed radio frequencyspectrum usable for LTE/LTE-A communications).

The shared radio frequency spectrum may include a radio frequencyspectrum for which transmitting apparatuses contend for access (e.g., aradio frequency spectrum that is available for unlicensed use, such asWi-Fi use, or a radio frequency spectrum that is available for use bymultiple operators in an equally shared or prioritized manner). In someexamples, the dedicated radio frequency spectrum or the shared radiofrequency spectrum may be used for LTE/LTE-A communications, asdescribed, for example, with reference to FIG. 1, 2, or 3. The receivermodule 1210 may in some cases include separate receivers for thededicated radio frequency spectrum and the shared radio frequencyspectrum. The separate receivers may, in some examples, take the form ofan LTE/LTE-A receiver module for communicating over the dedicated radiofrequency spectrum (e.g., LTE/LTE-A receiver module for dedicated RFspectrum 1212), and an LTE/LTE-A receiver module for communicating overthe shared radio frequency spectrum (e.g., LTE/LTE-A receiver module forshared RF spectrum 1214). The receiver module 1210, including theLTE/LTE-A receiver module for dedicated RF spectrum 1212 or theLTE/LTE-A receiver module for shared RF spectrum 1214, may be used toreceive various types of data or control signals (i.e., transmissions)over one or more communication links of a wireless communication system,such as one or more communication links of the wireless communicationsystem 100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the dedicated radiofrequency spectrum or the shared radio frequency spectrum.

In some examples, the transmitter module 1230 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum or the shared radiofrequency spectrum. The transmitter module 1230 may in some casesinclude separate transmitters for the dedicated radio frequency spectrumand the shared radio frequency spectrum. The separate transmitters may,in some examples, take the form of an LTE/LTE-A transmitter module forcommunicating over the dedicated radio frequency spectrum (e.g.,LTE/LTE-A transmitter module for dedicated RF spectrum 1232), and anLTE/LTE-A transmitter module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A transmitter module for shared RFspectrum 1234). The transmitter module 1230, including the LTE/LTE-Atransmitter module for dedicated RF spectrum 1232 or the LTE/LTE-Atransmitter module for shared RF spectrum 1234, may be used to transmitvarious types of data or control signals (i.e., transmissions) over oneor more communication links of a wireless communication system, such asone or more communication links of the wireless communication system100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the first radio frequencyspectrum or the second radio frequency spectrum.

In some examples, the wireless communication management module 1220 maybe used to manage one or more aspects of wireless communication for theapparatus 1215. In some examples, the wireless communication managementmodule 1220 may include an ACK/NAK payload size determination module1235 or an ACK/NAK payload format selection module 1240.

In some examples, the ACK/NAK payload size determination module 1235 maybe used to determine, based at least in part on a number of downlink CCsscheduled for a UE during a reporting interval, a number of bits to beincluded in a PUCCH ACK/NAK payload for the reporting interval.

In some examples, the ACK/NAK payload format selection module 1240 mayinclude a ACK/NAK payload size comparison module 1245. The ACK/NAKpayload size comparison module 1245 may be used to compare the number ofbits to be included in the PUCCH ACK/NAK payload to a plurality of bitranges. The ACK/NAK payload format selection module 1240 may then selecta format of the PUCCH ACK/NAK payload based at least in part on thecomparison performed by the ACK/NAK payload size comparison module 1245.In some examples, the selected format of the PUCCH ACK/NAK payload maybe based at least in part on a format including two reference signalsymbol periods per slot of a subframe.

In some examples, the format of the PUCCH ACK/NAK payload selected bythe ACK/NAK payload format selection module 1240 may be based at leastin part on a format including two reference signal symbol periods perslot (e.g., when the selected format is for a transmission, in a slot ofa subframe, with a normal CP). In some examples, the format of the PUCCHACK/NAK payload selected by the ACK/NAK payload format selection module1240 may be based at least in part on a format including one referencesignal symbol period per slot (e.g., when the selected format is for atransmission, in a slot of a subframe, with an extended CP).

In some examples, the format of the PUCCH ACK/NAK payload selected bythe ACK/NAK payload format selection module 1240 may include a UEmultiplexing density, within a RB, of at least four UEs (e.g., four orfive UEs). Such a format (i.e., a first format) may be selected, forexample, when the number of bits to be included in the ACK/NAK payloadis 21 or fewer bits (or from 1 to 21 bits) and a RB is configured asdescribed with reference to FIG. 4 or 5.

In some examples, the format of the PUCCH ACK/NAK payload selected bythe ACK/NAK payload format selection module 1240 may include a UEmultiplexing density, within a RB, of two UEs. The selected format mayalso include at least two groups of symbol periods, where each of the atleast two groups of symbol periods includes at least one symbol, andwhere spreading is applied independently within each of the at least twogroups of symbol periods. Such a format (i.e., a second format) may beselected, for example, when the number of bits to be included in theACK/NAK payload is 60 or fewer bits (or from 22 to 60 bits) and a RB isconfigured as described with reference to FIG. 4 or 5.

In a first example of the second format, a spreading factor of three maybe applied to a first group of three symbol periods and a spreadingfactor of two may be applied to a second group of two symbol periods,and two of three OCCs may be used when applying the spreading factor ofthree. In a second example of the second format, a first spreadingfactor of two may be applied to a first group of one symbol period, asecond spreading factor of two may be applied to a second group of twosymbol periods, and a third spreading factor of two may be appliedwithin a third group of two symbol periods. In the second example of thesecond format, the first spreading factor may be applied using a Walshcode or using elements of an orthogonal FFT matrix. In a third exampleof the second format, each spreading factor of a plurality of spreadingfactors of two may be applied to a respective symbol period of aplurality of symbol periods. In the third example of the second format,each spreading factor of the plurality of spreading factors of two maybe applied using a Walsh code or using elements of an orthogonal FFTmatrix.

In some examples, the format of the PUCCH ACK/NAK payload selected bythe ACK/NAK payload format selection module 1240 may include no UEmultiplexing within a RB, no spreading factor, and an RB allocation persymbol period of one. Such a format (i.e., a third format) may beselected, for example, when the number of bits to be included in theACK/NAK payload is 120 or fewer bits (or from 61 to 120 bits) and a RBis configured as described with reference to FIG. 4 or 5.

In some examples, the format of the PUCCH ACK/NAK payload selected bythe ACK/NAK payload format selection module 1240 may include no UEmultiplexing within a RB, no spreading factor, and an RB allocation persymbol period of two. Such a format (i.e., a fourth format) may beselected, for example, when the number of bits to be included in theACK/NAK payload is 240 or fewer bits (or from 121 to 240 bits) and a RBis configured as described with reference to FIG. 4 or 5.

In some examples, the format of the PUCCH ACK/NAK payload selected bythe ACK/NAK payload format selection module 1240 may include no UEmultiplexing within a RB, no spreading factor, and an RB allocation persymbol period of three. Such a format (i.e., a fifth format) may beselected, for example, when the number of bits to be included in theACK/NAK payload is 360 or fewer bits (or from 241 to 360 bits) and a RBis configured as described with reference to FIG. 4 or 5.

FIG. 13 shows a block diagram 1300 of an apparatus 1315 for use inwireless communication, in accordance with various aspects of thepresent disclosure. The apparatus 1315 may be an example of aspects ofone or more of the UEs 115, 215, 215-a, 215-b, 215-c, or 315 describedwith reference to FIG. 1, 2, or 3, or aspects of the apparatus 1115 or1215 described with reference to FIG. 11 or 12. The apparatus 1315 mayalso be or include a processor. The apparatus 1315 may include areceiver module 1310, a wireless communication management module 1320,or a transmitter module 1330. Each of these modules may be incommunication with each other.

The modules of the apparatus 1315 may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each module may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver module 1310 may include at least one RFreceiver, such as at least one RF receiver operable to receivetransmissions over a dedicated radio frequency spectrum or a sharedradio frequency spectrum. The dedicated radio frequency spectrum mayinclude a radio frequency spectrum for which transmitting apparatusesmay not contend for access (e.g., a radio frequency spectrum licensed toparticular users for particular uses, such as a licensed radio frequencyspectrum usable for LTE/LTE-A communications). The shared radiofrequency spectrum may include a radio frequency spectrum for whichtransmitting apparatuses contend for access (e.g., a radio frequencyspectrum that is available for unlicensed use, such as Wi-Fi use, or aradio frequency spectrum that is available for use by multiple operatorsin an equally shared or prioritized manner). In some examples, thededicated radio frequency spectrum or the shared radio frequencyspectrum may be used for LTE/LTE-A communications, as described, forexample, with reference to FIG. 1, 2, or 3. The receiver module 1310 mayin some cases include separate receivers for the dedicated radiofrequency spectrum and the shared radio frequency spectrum. The separatereceivers may, in some examples, take the form of an LTE/LTE-A receivermodule for communicating over the dedicated radio frequency spectrum(e.g., LTE/LTE-A receiver module for dedicated RF spectrum 1312), and anLTE/LTE-A receiver module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A receiver module for shared RFspectrum 1314). The receiver module 1310, including the LTE/LTE-Areceiver module for dedicated RF spectrum 1312 or the LTE/LTE-A receivermodule for shared RF spectrum 1314, may be used to receive various typesof data or control signals (i.e., transmissions) over one or morecommunication links of a wireless communication system, such as one ormore communication links of the wireless communication system 100, 200,or 300 described with reference to FIG. 1, 2, or 3. The communicationlinks may be established over the dedicated radio frequency spectrum orthe shared radio frequency spectrum.

In some examples, the transmitter module 1330 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum or the shared radiofrequency spectrum. The transmitter module 1330 may in some casesinclude separate transmitters for the dedicated radio frequency spectrumand the shared radio frequency spectrum. The separate transmitters may,in some examples, take the form of an LTE/LTE-A transmitter module forcommunicating over the dedicated radio frequency spectrum (e.g.,LTE/LTE-A transmitter module for dedicated RF spectrum 1332), and anLTE/LTE-A transmitter module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A transmitter module for shared RFspectrum 1334). The transmitter module 1330, including the LTE/LTE-Atransmitter module for dedicated RF spectrum 1332 or the LTE/LTE-Atransmitter module for shared RF spectrum 1334, may be used to transmitvarious types of data or control signals (i.e., transmissions) over oneor more communication links of a wireless communication system, such asone or more communication links of the wireless communication system100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the first radio frequencyspectrum or the second radio frequency spectrum.

In some examples, the wireless communication management module 1320 maybe used to manage one or more aspects of wireless communication for theapparatus 1315. In some examples, the wireless communication managementmodule 1320 may include a downlink CC identification module 1345, adownlink CC subset identification module 1350, an ACK/NAK payload sizedetermination module 1335, an ACK/NAK payload format selection module1340, or an ACK/NAK payload transmission management module 1355.

In some examples, the downlink CC identification module 1345 may be usedto identify an allocation of a plurality of downlink CCs for a UE.

In some examples, the downlink CC subset identification module 1350 maybe used to identify at least a first subset of downlink CCs within theplurality of downlink CCs. Additional subsets of downlink CCs may alsobe identified (e.g., a second subset of downlink CCs, etc.).

In some examples, the ACK/NAK payload size determination module 1335 maybe used to determine, based at least in part on a number of downlink CCsin the first subset of downlink CCs that are scheduled for the UE duringa reporting interval, a number of bits to be included in a first PUCCHACK/NAK payload for the reporting interval. The ACK/NAK payload sizedetermination module 1335 may also be used to determine, based at leastin part on a number of downlink CCs in each of one or more additionalsubsets of downlink CCs that are scheduled for the UE during a reportinginterval (e.g., for the second subset of downlink CCs), a number of bitsto be included in each of the one or more additional PUCCH ACK/NAKpayloads (e.g., a second PUCCH ACK/NAK payload) for the reportinginterval.

In some examples, the ACK/NAK payload format selection module 1340 maybe used to select, based at least in part on the determined number ofbits for the first PUCCH ACK/NAK payload, a format of the first PUCCHACK/NAK payload. The ACK/NAK payload format selection module 1340 mayalso be used to select, based at least in part on the determined numberof bits for the PUCCH ACK/NAK payload(s) of each of the one or moreadditional subsets of downlink CCs (e.g., the second subset of downlinkCCs), a format of each of the one or more additional PUCCH ACK/NAKpayloads (e.g., the second PUCCH ACK/NAK payload).

In some examples, the ACK/NAK payload transmission management module1355 may be used to transmit the first PUCCH ACK/NAK payload on a firstuplink CC, and transmit an additional PUCCH ACK/NAK payload (e.g., thesecond ACK/NAK payload) on a second uplink CC. Alternatively, theACK/NAK payload transmission management module 1355 may be used totransmit the first PUCCH ACK/NAK payload and an additional ACK/NAKpayload (e.g., the second ACK/NAK payload) on a same uplink CC.

FIG. 14 shows a block diagram 1400 of an apparatus 1415 for use inwireless communication, in accordance with various aspects of thepresent disclosure. The apparatus 1415 may be an example of aspects ofone or more of the base stations 105, 205, 205-a, or 305 described withreference to FIG. 1, 2, or 3, or aspects of the apparatus 1115 or 1215described with reference to FIG. 11 or 12. The apparatus 1415 may alsobe or include a processor. The apparatus 1415 may include a receivermodule 1410, a wireless communication management module 1420, or atransmitter module 1430. Each of these modules may be in communicationwith each other.

The modules of the apparatus 1415 may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each module may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver module 1410 may include at least one RFreceiver, such as at least one RF receiver operable to receivetransmissions over a dedicated radio frequency spectrum or a sharedradio frequency spectrum. The dedicated radio frequency spectrum mayinclude a radio frequency spectrum for which transmitting apparatusesmay not contend for access (e.g., a radio frequency spectrum licensed toparticular users for particular uses, such as a licensed radio frequencyspectrum usable for LTE/LTE-A communications). The shared radiofrequency spectrum may include a radio frequency spectrum for whichtransmitting apparatuses contend for access (e.g., a radio frequencyspectrum that is available for unlicensed use, such as Wi-Fi use, or aradio frequency spectrum that is available for use by multiple operatorsin an equally shared or prioritized manner). In some examples, thededicated radio frequency spectrum or the shared radio frequencyspectrum may be used for LTE/LTE-A communications, as described, forexample, with reference to FIG. 1, 2, or 3. The receiver module 1410 mayin some cases include separate receivers for the dedicated radiofrequency spectrum and the shared radio frequency spectrum. The separatereceivers may, in some examples, take the form of an LTE/LTE-A receivermodule for communicating over the dedicated radio frequency spectrum(e.g., LTE/LTE-A receiver module for dedicated RF spectrum 1412), and anLTE/LTE-A receiver module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A receiver module for shared RFspectrum 1414). The receiver module 1410, including the LTE/LTE-Areceiver module for dedicated RF spectrum 1412 or the LTE/LTE-A receivermodule for shared RF spectrum 1414, may be used to receive various typesof data or control signals (i.e., transmissions) over one or morecommunication links of a wireless communication system, such as one ormore communication links of the wireless communication system 100, 200,or 300 described with reference to FIG. 1, 2, or 3. The communicationlinks may be established over the dedicated radio frequency spectrum orthe shared radio frequency spectrum.

In some examples, the transmitter module 1430 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum or the shared radiofrequency spectrum. The transmitter module 1430 may in some casesinclude separate transmitters for the dedicated radio frequency spectrumand the shared radio frequency spectrum. The separate transmitters may,in some examples, take the form of an LTE/LTE-A transmitter module forcommunicating over the dedicated radio frequency spectrum (e.g.,LTE/LTE-A transmitter module for dedicated RF spectrum 1432), and anLTE/LTE-A transmitter module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A transmitter module for shared RFspectrum 1434). The transmitter module 1430, including the LTE/LTE-Atransmitter module for dedicated RF spectrum 1432 or the LTE/LTE-Atransmitter module for shared RF spectrum 1434, may be used to transmitvarious types of data or control signals (i.e., transmissions) over oneor more communication links of a wireless communication system, such asone or more communication links of the wireless communication system100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the first radio frequencyspectrum or the second radio frequency spectrum.

In some examples, the wireless communication management module 1420 maybe used to manage one or more aspects of wireless communication for theapparatus 1415. In some examples, the wireless communication managementmodule 1420 may include a downlink CC allocation module 1445, a downlinkCC subset configuration module 1450, an ACK/NAK payload sizedetermination module 1435, or an ACK/NAK payload format selection module1440.

In some examples, the downlink CC allocation module 1445 may be used toallocate a plurality of downlink CCs for a UE.

In some examples, the downlink CC subset configuration module 1450 maybe used to configure at least two groups of downlink CCs (e.g.,configure at least a first subset of downlink CCs and a second subset ofdownlink CCs within the plurality of downlink CCs).

In some examples, the ACK/NAK payload size determination module 1435 maybe used to determine, for each group of downlink CCs, and based at leastin part on a number of downlink CCs that are scheduled for the UE duringa reporting interval, a number of bits to be included in a PUCCH ACK/NAKpayload for the group of downlink CCs for the reporting interval. Thus,for example, a first number of bits to be included in a first PUCCHACK/NAK payload for a first group of downlink CCs may be determined, anda second number of bits to be included in a second PUCCH ACK/NAK payloadfor a second group of downlink CCs may be determined.

In some examples, the ACK/NAK payload format selection module 1440 maybe used to select, for each PUCCH ACK/NAK payload, and based at least inpart on the determined number of bits for the PUCCH ACK/NAK payload, aformat of the first PUCCH ACK/NAK payload. That is, a format of a PUCCHACK/NAK payload may be selected for each of the at least two groups ofdownlink CCs. Also or alternatively, a format of a PUCCH ACK/NAK payloadmay be selected considering bundling of ACK/NAK bits for the downlinkCCs within each of the at least two groups of downlink CCs.

FIG. 15 shows a block diagram 1500 of an apparatus 1515 for use inwireless communication, in accordance with various aspects of thepresent disclosure. The apparatus 1515 may be an example of aspects ofone or more of the UEs 115, 215, 215-a, 215-b, 215-c, or 315 describedwith reference to FIG. 1, 2, or 3, or aspects of the apparatus 1115,1215, or 1315 described with reference to FIG. 11, 12, or 13. Theapparatus 1515 may also be or include a processor. The apparatus 1515may include a receiver module 1510, a wireless communication managementmodule 1520, or a transmitter module 1530. Each of these modules may bein communication with each other.

The modules of the apparatus 1515 may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each module may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver module 1510 may include at least one RFreceiver, such as at least one RF receiver operable to receivetransmissions over a dedicated radio frequency spectrum or a sharedradio frequency spectrum. The dedicated radio frequency spectrum mayinclude a radio frequency spectrum for which transmitting apparatusesmay not contend for access (e.g., a radio frequency spectrum licensed toparticular users for particular uses, such as a licensed radio frequencyspectrum usable for LTE/LTE-A communications). The shared radiofrequency spectrum may include a radio frequency spectrum for whichtransmitting apparatuses contend for access (e.g., a radio frequencyspectrum that is available for unlicensed use, such as Wi-Fi use, or aradio frequency spectrum that is available for use by multiple operatorsin an equally shared or prioritized manner). In some examples, thededicated radio frequency spectrum or the shared radio frequencyspectrum may be used for LTE/LTE-A communications, as described, forexample, with reference to FIG. 1, 2, or 3. The receiver module 1510 mayin some cases include separate receivers for the dedicated radiofrequency spectrum and the shared radio frequency spectrum. The separatereceivers may, in some examples, take the form of an LTE/LTE-A receivermodule for communicating over the dedicated radio frequency spectrum(e.g., LTE/LTE-A receiver module for dedicated RF spectrum 1512), and anLTE/LTE-A receiver module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A receiver module for shared RFspectrum 1514). The receiver module 1510, including the LTE/LTE-Areceiver module for dedicated RF spectrum 1512 or the LTE/LTE-A receivermodule for shared RF spectrum 1514, may be used to receive various typesof data or control signals (i.e., transmissions) over one or morecommunication links of a wireless communication system, such as one ormore communication links of the wireless communication system 100, 200,or 300 described with reference to FIG. 1, 2, or 3. The communicationlinks may be established over the dedicated radio frequency spectrum orthe shared radio frequency spectrum.

In some examples, the transmitter module 1530 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum or the shared radiofrequency spectrum. The transmitter module 1530 may in some casesinclude separate transmitters for the dedicated radio frequency spectrumand the shared radio frequency spectrum. The separate transmitters may,in some examples, take the form of an LTE/LTE-A transmitter module forcommunicating over the dedicated radio frequency spectrum (e.g.,LTE/LTE-A transmitter module for dedicated RF spectrum 1532), and anLTE/LTE-A transmitter module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A transmitter module for shared RFspectrum 1534). The transmitter module 1530, including the LTE/LTE-Atransmitter module for dedicated RF spectrum 1532 or the LTE/LTE-Atransmitter module for shared RF spectrum 1534, may be used to transmitvarious types of data or control signals (i.e., transmissions) over oneor more communication links of a wireless communication system, such asone or more communication links of the wireless communication system100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the first radio frequencyspectrum or the second radio frequency spectrum.

In some examples, the wireless communication management module 1520 maybe used to manage one or more aspects of wireless communication for theapparatus 1515. In some examples, the wireless communication managementmodule 1520 may include a downlink grant processing module 1545, anACK/NAK payload size determination module 1535, or an ACK/NAK payloadformat selection module 1540.

In some examples, the downlink grant processing module 1545 may be usedto receive a number of downlink grants indicating the downlink CCsscheduled for a UE, and to receive with each of the downlink grants arespective DAI. The downlink grant processing module 1545 may include aDAI processing module 1550 that may be used to receive the DAI(s).

In some examples, the ACK/NAK payload size determination module 1535 maybe used to determine, based at least in part on a number of downlink CCsscheduled for the UE during a reporting interval, a number of bits to beincluded in a PUCCH ACK/NAK payload for the reporting interval.

In some examples, the ACK/NAK payload format selection module 1540 maybe used to select, based at least in part on the determined number ofbits, a format of the PUCCH ACK/NAK payload.

In some examples of the apparatus 1515, the respective DAI for adownlink grant may indicate a bit mapping and resource selection, in thePUCCH ACK/NAK payload, for acknowledging/non-acknowledging eachtransmission over each downlink CC scheduled in the downlink grant.

In some examples of the apparatus 1515, the respective DAI for adownlink grant may include a sequence number indicating a relationshipbetween at least one downlink CC scheduled in the downlink grant and atleast one downlink CC scheduled in another downlink grant. In theseexamples, the DAI processing module 1550 may determine, based at leastin part on the sequence number, a bit mapping and resource selection, inthe PUCCH ACK/NAK payload, for acknowledging/non-acknowledging eachtransmission over each downlink CC scheduled in the downlink grant.

FIG. 16 shows a block diagram 1600 of an apparatus 1615 for use inwireless communication, in accordance with various aspects of thepresent disclosure. The apparatus 1615 may be an example of aspects ofone or more of the base stations 105, 205, 205-a, or 305 described withreference to FIG. 1, 2, or 3, or aspects of the apparatus 1115, 1215, or1415 described with reference to FIG. 11, 12, or 14. The apparatus 1615may also be or include a processor. The apparatus 1615 may include areceiver module 1610, a wireless communication management module 1620,or a transmitter module 1630. Each of these modules may be incommunication with each other.

The modules of the apparatus 1615 may, individually or collectively, beimplemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each module may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver module 1610 may include at least one RFreceiver, such as at least one RF receiver operable to receivetransmissions over a dedicated radio frequency spectrum or a sharedradio frequency spectrum. The dedicated radio frequency spectrum mayinclude a radio frequency spectrum for which transmitting apparatusesmay not contend for access (e.g., a radio frequency spectrum licensed toparticular users for particular uses, such as a licensed radio frequencyspectrum usable for LTE/LTE-A communications).

The shared radio frequency spectrum may include a radio frequencyspectrum for which transmitting apparatuses contend for access (e.g., aradio frequency spectrum that is available for unlicensed use, such asWi-Fi use, or a radio frequency spectrum that is available for use bymultiple operators in an equally shared or prioritized manner). In someexamples, the dedicated radio frequency spectrum or the shared radiofrequency spectrum may be used for LTE/LTE-A communications, asdescribed, for example, with reference to FIG. 1, 2, or 3. The receivermodule 1610 may in some cases include separate receivers for thededicated radio frequency spectrum and the shared radio frequencyspectrum. The separate receivers may, in some examples, take the form ofan LTE/LTE-A receiver module for communicating over the dedicated radiofrequency spectrum (e.g., LTE/LTE-A receiver module for dedicated RFspectrum 1612), and an LTE/LTE-A receiver module for communicating overthe shared radio frequency spectrum (e.g., LTE/LTE-A receiver module forshared RF spectrum 1614). The receiver module 1610, including theLTE/LTE-A receiver module for dedicated RF spectrum 1612 or theLTE/LTE-A receiver module for shared RF spectrum 1614, may be used toreceive various types of data or control signals (i.e., transmissions)over one or more communication links of a wireless communication system,such as one or more communication links of the wireless communicationsystem 100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the dedicated radiofrequency spectrum or the shared radio frequency spectrum.

In some examples, the transmitter module 1630 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the dedicated radio frequency spectrum or the shared radiofrequency spectrum. The transmitter module 1630 may in some casesinclude separate transmitters for the dedicated radio frequency spectrumand the shared radio frequency spectrum. The separate transmitters may,in some examples, take the form of an LTE/LTE-A transmitter module forcommunicating over the dedicated radio frequency spectrum (e.g.,LTE/LTE-A transmitter module for dedicated RF spectrum 1632), and anLTE/LTE-A transmitter module for communicating over the shared radiofrequency spectrum (e.g., LTE/LTE-A transmitter module for shared RFspectrum 1634). The transmitter module 1630, including the LTE/LTE-Atransmitter module for dedicated RF spectrum 1632 or the LTE/LTE-Atransmitter module for shared RF spectrum 1634, may be used to transmitvarious types of data or control signals (i.e., transmissions) over oneor more communication links of a wireless communication system, such asone or more communication links of the wireless communication system100, 200, or 300 described with reference to FIG. 1, 2, or 3. Thecommunication links may be established over the first radio frequencyspectrum or the second radio frequency spectrum.

In some examples, the wireless communication management module 1620 maybe used to manage one or more aspects of wireless communication for theapparatus 1615. In some examples, the wireless communication managementmodule 1620 may include a downlink grant transmission management module1645, an ACK/NAK payload size determination module 1635, an ACK/NAKpayload format selection module 1640, or an ACK/NAK payload receptionmanagement module 1650.

In some examples, the downlink grant transmission management module 1645may be used to transmit, to a UE, a plurality of downlink grantsindicating the downlink CCs scheduled for the UE, and to transmit aplurality of DAIs, where each of the plurality of downlink grantsincludes a respective one of the DAIs in the plurality of DAIs. Thedownlink grant transmission management module 1645 may include a DAItransmission management module 1655 that may be used to transmit theplurality of DAIs.

In some examples, the ACK/NAK payload size determination module 1635 maybe used to determine, based at least in part on a number of downlink CCsscheduled for the UE during a reporting interval, a number of bits to beincluded in a PUCCH ACK/NAK payload for the reporting interval.

In some examples, the ACK/NAK payload format selection module 1640 maybe used to select, based at least in part on the determined number ofbits, a format of the PUCCH ACK/NAK payload.

In some examples of the apparatus 1615, the respective DAI for adownlink grant may indicate a bit mapping and resource selection, in thePUCCH ACK/NAK payload, for acknowledging/non-acknowledging eachtransmission over each downlink CC scheduled in the downlink grant.

In some examples of the apparatus 1615, the plurality of DAIs mayinclude a plurality of sequence numbers. In these examples, the DAItransmission management module 1655 may introduce sequencediscontinuities in the plurality of sequence numbers, to increase thenumber of bits to be included in the PUCCH ACK/NAK payload.

In some examples, the ACK/NAK payload reception management module 1050may be used to receive the PUCCH ACK/NAK payload and use a set ofACK/NAK bits in the PUCCH ACK/NAK payload, which set of ACK/NAK bitscorrespond to the sequence discontinuities introduced by the DAItransmission management module 1655, as a virtual CRC. In some examples,the DAI transmission management module 1655 may introduce sequencediscontinuities in the plurality of sequence numbers to both increasethe number of bits to be included in the PUCCH ACK/NAK payload and toincrease the length of the virtual CRC.

In some examples, aspects of two or more of the apparatuses 1100, 1200,1300, or 1500 described with reference to FIG. 11, 12, 13, or 15 may becombined, or aspects of two or more of the apparatuses 1100, 1200, 1400,or 1600 described with reference to FIG. 11, 12, 14, or 16 may becombined.

FIG. 17 shows a block diagram 1700 of a UE 1715 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The UE 1715 may have various configurations and may beincluded or be part of a personal computer (e.g., a laptop computer, anetbook computer, a tablet computer, etc.), a cellular telephone, a PDA,a digital video recorder (DVR), an internet appliance, a gaming console,an e-reader, etc. The UE 1715 may, in some examples, have an internalpower supply (not shown), such as a small battery, to facilitate mobileoperation. In some examples, the UE 1715 may be an example of aspects ofone or more of the UE 115, 215, 215-a, 215-b, 215-c, or 315 describedwith reference to FIG. 1, 2, or 3, or aspects of one or more of theapparatuses 1115, 1215, 1315, or 1515 described with reference to FIG.11, 12, 13, or 15. The UE 1715 may be configured to implement at leastsome of the UE or apparatus features and functions described withreference to FIG. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 15.

The UE 1715 may include a UE processor module 1710, a UE memory module1720, at least one UE transceiver module (represented by UE transceivermodule(s) 1730), at least one UE antenna (represented by UE antenna(s)1740), or a UE wireless communication management module 1760. Each ofthese components may be in communication with each other, directly orindirectly, over one or more buses 1735.

The UE memory module 1720 may include random access memory (RAM) orread-only memory (ROM). The UE memory module 1720 may storecomputer-readable, computer-executable code 1725 containing instructionsthat are configured to, when executed, cause the UE processor module1710 to perform various functions described herein related to wirelesscommunication, including the selection of a format of a PUCCH ACK/NAKpayload based at least in part on a number of bits to be included in thePUCCH ACK/NAK payload. Alternatively, the code 1725 may not be directlyexecutable by the UE processor module 1710 but be configured to causethe UE 1715 (e.g., when compiled and executed) to perform various of thefunctions described herein.

The UE processor module 1710 may include an intelligent hardware device,e.g., a central processing unit (CPU), a microcontroller, an ASIC, etc.The UE processor module 1710 may process information received throughthe UE transceiver module(s) 1730 or information to be sent to the UEtransceiver module(s) 1730 for transmission through the UE antenna(s)1740. The UE processor module 1710 may handle, alone or in connectionwith the UE wireless communication management module 1760, variousaspects of communicating over (or managing communications over) alicensed radio frequency spectrum band (e.g., a radio frequency spectrumband for which apparatuses do not contend for access because the radiofrequency spectrum band is licensed to particular users for particularuses, such as a licensed radio frequency spectrum band usable forLTE/LTE-A communications) or a shared radio frequency spectrum band(e.g., a radio frequency spectrum band for which apparatuses contend foraccess because the radio frequency spectrum band is available forunlicensed use, such as Wi-Fi use).

The UE transceiver module(s) 1730 may include a modem configured tomodulate packets and provide the modulated packets to the UE antenna(s)1740 for transmission, and to demodulate packets received from the UEantenna(s) 1740. The UE transceiver module(s) 1730 may, in someexamples, be implemented as one or more UE transmitter modules and oneor more separate UE receiver modules. The UE transceiver module(s) 1730may support communications in the licensed radio frequency spectrum bandor the shared radio frequency spectrum band. The UE transceivermodule(s) 1730 may be configured to communicate bi-directionally, viathe UE antenna(s) 1740, with one or more of the base stations 105, 205,205-a, or 305 described with reference to FIG. 1, 2, or 3, or one ormore of the apparatuses 1115, 1215, 1415, or 1615 described withreference to FIG. 11, 12, 14, or 16. While the UE 1715 may include asingle UE antenna, there may be examples in which the UE 1715 mayinclude multiple UE antennas 1740.

The UE state module 1750 may be used, for example, to manage transitionsof the UE 1715 between an RRC idle state and an RRC connected state, andmay be in communication with other components of the UE 1715, directlyor indirectly, over the one or more buses 1735. The UE state module1750, or portions of it, may include a processor, or some or all of thefunctions of the UE state module 1750 may be performed by the UEprocessor module 1710 or in connection with the UE processor module1710.

The UE wireless communication management module 1760 may be configuredto perform or control some or all of the UE or apparatus features orfunctions described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, or 15 related to wireless communication over a licensedradio frequency spectrum band or a shared radio frequency spectrum band.For example, the UE wireless communication management module 1760 may beconfigured to support a supplemental downlink mode, a carrieraggregation mode, a standalone mode, or a dual-connectivity mode usingthe licensed radio frequency spectrum band or the shared radio frequencyspectrum band. The UE wireless communication management module 1760 mayinclude a UE LTE/LTE-A module for licensed RF spectrum band 1765configured to handle LTE/LTE-A communications in the licensed radiofrequency spectrum band, and a UE LTE/LTE-A module for shared RFspectrum band 1770 configured to handle LTE/LTE-A communications in theshared radio frequency spectrum band. The UE wireless communicationmanagement module 1760, or portions of it, may include a processor, orsome or all of the functions of the UE wireless communication managementmodule 1760 may be performed by the UE processor module 1710 or inconnection with the UE processor module 1710. In some examples, the UEwireless communication management module 1760 may be an example of thewireless communication management module 1120, 1220, 1320, or 1520described with reference to FIG. 11, 12, 13, or 15.

FIG. 18 shows a block diagram 1800 of a base station 1805 (e.g., a basestation forming part or all of an eNB) for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. In some examples, the base station 1805 may be an example ofone or more aspects of the base station 105, 205, 205-a, or 305described with reference to FIG. 1, 2, or 3. The base station 1805 maybe configured to implement or facilitate at least some of the basestation features and functions described with reference to FIG. 1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 14, or 16.

The base station 1805 may include a base station processor module 1810,a base station memory module 1820, at least one base station transceivermodule (represented by base station transceiver module(s) 1850), atleast one base station antenna (represented by base station antenna(s)1855), or a base station wireless communication management module 1860.The base station 1805 may also include one or more of a base stationcommunications module 1830 or a network communications module 1840. Eachof these components may be in communication with each other, directly orindirectly, over one or more buses 1835.

The base station memory module 1820 may include RAM or ROM. The basestation memory module 1820 may store computer-readable,computer-executable code 1825 containing instructions that areconfigured to, when executed, cause the base station processor module1810 to perform various functions described herein related to wirelesscommunication, including the selection of a format of a PUCCH ACK/NAKpayload based at least in part on a number of bits to be included in thePUCCH ACK/NAK payload. Alternatively, the code 1825 may not be directlyexecutable by the base station processor module 1810 but be configuredto cause the base station 1805 (e.g., when compiled and executed) toperform various of the functions described herein.

The base station processor module 1810 may include an intelligenthardware device, e.g., a CPU, a microcontroller, an ASIC, etc. The basestation processor module 1810 may process information received throughthe base station transceiver module(s) 1850, the base stationcommunications module 1830, or the network communications module 1840.The base station processor module 1810 may also process information tobe sent to the transceiver module(s) 1850 for transmission through theantenna(s) 1855, to the base station communications module 1830, fortransmission to one or more other base stations 1805-a and 1805-b, or tothe network communications module 1840 for transmission to a corenetwork 1845, which may be an example of one or more aspects of the corenetwork 130 described with reference to FIG. 1. The base stationprocessor module 1810 may handle, alone or in connection with the basestation wireless communication management module 1860, various aspectsof communicating over (or managing communications over) a licensed radiofrequency spectrum band (e.g., a radio frequency spectrum band for whichapparatuses do not contend for access because the radio frequencyspectrum band is licensed to particular users for particular uses, suchas a licensed radio frequency spectrum band usable for LTE/LTE-Acommunications) or a shared radio frequency spectrum band (e.g., a radiofrequency spectrum band for which apparatuses contend for access becausethe radio frequency spectrum band is available for unlicensed use, suchas Wi-Fi use).

The base station transceiver module(s) 1850 may include a modemconfigured to modulate packets and provide the modulated packets to thebase station antenna(s) 1855 for transmission, and to demodulate packetsreceived from the base station antenna(s) 1855. The base stationtransceiver module(s) 1850 may, in some examples, be implemented as oneor more base station transmitter modules and one or more separate basestation receiver modules. The base station transceiver module(s) 1850may support communications in the licensed radio frequency spectrum bandor the shared radio frequency spectrum band. The base stationtransceiver module(s) 1850 may be configured to communicatebi-directionally, via the antenna(s) 1855, with one or more UEs orapparatuses, such as one or more of the UEs 115, 215, 215-a, 215-b,215-c, or 1715 described with reference to FIG. 1, 2, or 17, or one ormore of the apparatuses 1115, 1215, 1315, or 1515 described withreference to FIG. 11, 12, 13, or 15. The base station 1805 may, forexample, include multiple base station antennas 1855 (e.g., an antennaarray). The base station 1805 may communicate with the core network 1845through the network communications module 1840. The base station 1805may also communicate with other base stations, such as the base stations1805-a and 1805-b, using the base station communications module 1830.

The base station wireless communication management module 1860 may beconfigured to perform or control some or all of the features orfunctions described with reference to FIG. 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 14, or 16 related to wireless communication over a licensedradio frequency spectrum band or a shared radio frequency spectrum band.For example, the base station wireless communication management module1860 may be configured to support a supplemental downlink mode, acarrier aggregation mode, a standalone mode using, or adual-connectivity mode using the licensed radio frequency spectrum bandor the shared radio frequency spectrum band. The base station wirelesscommunication management module 1860 may include a base stationLTE/LTE-A module for licensed RF spectrum band 1865 configured to handleLTE/LTE-A communications in the licensed radio frequency spectrum band,and a base station LTE/LTE-A module for shared RF spectrum band 1870configured to handle LTE/LTE-A communications in the shared radiofrequency spectrum band. The base station wireless communicationmanagement module 1860, or portions of it, may include a processor, orsome or all of the functions of the base station wireless communicationmanagement module 1860 may be performed by the base station processormodule 1810 or in connection with the base station processor module1810. In some examples, the base station wireless communicationmanagement module 1860 may be an example of the wireless communicationmanagement module 1120, 1220, 1420, or 1620 described with reference toFIG. 11, 12, 14, or 16.

FIG. 19 is a block diagram of a multiple input/multiple output (MIMO)communication system 1900 including a base station 1905 and a UE 1915,in accordance with various aspects of the present disclosure. The MIMOcommunication system 1900 may illustrate aspects of the wirelesscommunication system 100, 200, or 300 described with reference to FIG.1, 2, or 3. The base station 1905 may be an example of aspects of thebase station 105, 205, 205-a, or 1805 described with reference to FIG.1, 2, or 18, or aspects of the apparatus 1115, 1215, 1415, or 1615described with reference to 11, 12, 14, or 16. The base station 1905 maybe equipped with antennas 1934 through 1935, and the UE 1915 may beequipped with antennas 1952 through 1953. In the MIMO communicationsystem 1900, the base station 1905 may be able to send data overmultiple communication links at the same time. Each communication linkmay be called a “layer” and the “rank” of the communication link mayindicate the number of layers used for communication. For example, in a2×2 MIMO communications system where base station 1905 transmits two“layers,” the rank of the communication link between the base station1905 and the UE 1915 is two.

At the base station 1905, a transmit processor 1920 may receive datafrom a data source. The transmit processor 1920 may process the data.The transmit processor 1920 may also generate control symbols orreference symbols. A transmit (Tx) MIMO processor 1930 may performspatial processing (e.g., precoding) on data symbols, control symbols,or reference symbols, if applicable, and may provide output symbolstreams to the transmit modulators 1932 through 1933. Each modulator1932 through 1933 may process a respective output symbol stream (e.g.,for OFDM, etc.) to obtain an output sample stream. Each modulator 1932through 1933 may further process (e.g., convert to analog, amplify,filter, and upconvert) the output sample stream to obtain a DL signal.In one example, DL signals from modulators 1932 through 1933 may betransmitted via the antennas 1934 through 1935, respectively.

The UE 1915 may be an example of aspects of the UE 115, 215, 215-a,215-b, 215-c, or 1715 described with reference to FIG. 1, 2, or 17, oraspects of the apparatus 1115, 1215, 1315, or 1515 described withreference to FIG. 11, 12, 13, or 15. At the UE 1915, the UE antennas1952 through 1953 may receive the DL signals from the base station 1905and may provide the received signals to the demodulators 1954 through1955, respectively. Each demodulator 1954 through 1955 may condition(e.g., filter, amplify, downconvert, and digitize) a respective receivedsignal to obtain input samples. Each demodulator 1954 through 1955 mayfurther process the input samples (e.g., for OFDM, etc.) to obtainreceived symbols. A MIMO detector 1956 may obtain received symbols fromall the demodulators 1954 through 1955, perform MIMO detection on thereceived symbols, if applicable, and provide detected symbols. A receive(Rx) processor 1958 may process (e.g., demodulate, deinterleave, anddecode) the detected symbols, providing decoded data for the UE 1915 toa data output, and provide decoded control information to a processor1980, or memory 1982.

The processor 1980 may in some cases execute stored instructions toinstantiate a wireless communication management module 1984. Thewireless communication management module 1984 may be an example ofaspects of the wireless communication management module 1120, 1220,1320, 1520, or 1760 described with reference to FIG. 11, 12, 13, 15, or17.

On the uplink (UL), at the UE 1915, a transmit processor 1964 mayreceive and process data from a data source. The transmit processor 1964may also generate reference symbols for a reference signal. The symbolsfrom the transmit processor 1964 may be precoded by a transmit MIMOprocessor 1966 if applicable, further processed by the modulators 1954through 1955 (e.g., for SC-FDMA, etc.), and be transmitted to the basestation 1905 in accordance with the transmission parameters receivedfrom the base station 1905. At the base station 1905, the UL signalsfrom the UE 1915 may be received by the antennas 1934 through 1935,processed by the demodulators 1932 through 1933, detected by a MIMOdetector 1936 if applicable, and further processed by a receiveprocessor 1938. The receive processor 1938 may provide decoded data to adata output and to the processor 1940 or memory 1942.

The processor 1940 may in some cases execute stored instructions toinstantiate a wireless communication management module 1986. Thewireless communication management module 1986 may be an example ofaspects of the wireless communication management module 1120, 1220,1420, 1620, or 1860 described with reference to FIG. 11, 12, 14, 16, or18.

The components of the UE 1915 may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Each of the noted modules may be ameans for performing one or more functions related to operation of theMIMO communication system 1900. Similarly, the components of the basestation 1905 may, individually or collectively, be implemented with oneor more ASICs adapted to perform some or all of the applicable functionsin hardware. Each of the noted components may be a means for performingone or more functions related to operation of the MIMO communicationsystem 1900.

FIG. 20 is a flow chart illustrating an exemplary method 2000 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2000 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 1715, or 1815 described with reference to FIG. 1, 2, 17, or 18,aspects of one or more of the base stations 105, 205, 205-a, 1805, or1905 described with reference to FIG. 1, 2, 18, or 19, or aspects of oneor more of the apparatuses 1115, 1215, 1315, 1415, 1515, or 1615described with reference to FIG. 11, 12, 13, 14, 15, or 16. In someexamples, a UE, base station, or apparatus may execute one or more setsof codes to control the functional elements of the UE, base station, orapparatus to perform the functions described below. Additionally oralternatively, the UE, base station, or apparatus may perform one ormore of the functions described below using special-purpose hardware.

At block 2005, the method 2000 may include determining, based at leastin part on a number of downlink CCs scheduled for a UE during areporting interval, a number of bits to be included in a PUCCH ACK/NAKpayload for the reporting interval. The operation(s) at block 2005 maybe performed using the wireless communication management module 1120,1220, 1320, 1420, 1520, 1620, 1760, 1860, 1984, or 1986 described withreference to FIG. 11, 12, 13, 14, 15, 16, 17, 18, or 19, or the ACK/NAKpayload size determination module 1135, 1235, 1335, 1435, 1535, or 1635described with reference to FIG. 11, 12, 13, 14, 15, or 16.

At block 2010, the method 2000 may include selecting, based at least inpart on the determined number of bits, a format of the PUCCH ACK/NAKpayload. The operation(s) at block 2010 may be performed using thewireless communication management module 1120, 1220, 1320, 1420, 1520,1620, 1760, 1860, 1984, or 1986 described with reference to FIG. 11, 12,13, 14, 15, 16, 17, 18, or 19, or the ACK/NAK payload format selectionmodule 1140, 1240, 1340, 1440, 1540, or 1640 described with reference toFIG. 11, 12, 13, 14, 15, or 16.

In some examples of the method 2000, selecting the format of the PUCCHACK/NAK payload may include selecting one of a plurality of predefinedformats for the PUCCH ACK/NAK payload. The predefined formats for thePUCCH ACK/NAK payload may include, for example, different combinationsof: UE multiplexing densities within a RB, spreading factors, or numbersof RBs allocated per symbol period. In some examples, each of thepredefined formats for the PUCCH ACK/NAK payload may be based at leastin part on a format including two reference signal symbol periods perslot (e.g., when the predefined formats are configured fortransmissions, in a slot of a subframe, with a normal CP). In someexamples, each of the predefined formats for the PUCCH ACK/NAK payloadmay be based at least in part on a format including one reference signalsymbol period per slot (e.g., when the predefined formats are configuredfor transmissions, in a slot of a subframe, with an extended CP).

In examples of the method 2000 performed by a UE, the method 2000 mayinclude receiving, at the UE, a number of downlink grants indicating thedownlink CCs scheduled for the UE. In these examples, selecting theformat of the PUCCH ACK/NAK payload may include selecting a format usedto transmit the PUCCH ACK/NAK payload.

In examples of the method 2000 performed by a base station, the method2000 may include transmitting, from a base station to the UE, aplurality of downlink grants indicating the downlink CCs scheduled forthe UE. In these examples of the method, selecting the format of thePUCCH ACK/NAK payload may include selecting a format used to decode thePUCCH ACK/NAK payload.

Thus, the method 2000 may provide for wireless communication. It shouldbe noted that the method 2000 is just one implementation and that theoperations of the method 2000 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 21 is a flow chart illustrating an exemplary method 2100 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2100 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 1715, or 1815 described with reference to FIG. 1, 2, 17, or 18,aspects of one or more of the base stations 105, 205, 205-a, 1805, or1905 described with reference to FIG. 1, 2, 18, or 19, or aspects of oneor more of the apparatuses 1115, 1215, 1315, 1415, 1515, or 1615described with reference to FIG. 11, 12, 13, 14, 15, or 16. In someexamples, a UE, base station, or apparatus may execute one or more setsof codes to control the functional elements of the UE, base station, orapparatus to perform the functions described below. Additionally oralternatively, the UE, base station, or apparatus may perform one ormore of the functions described below using special-purpose hardware.

At block 2105, the method 200 may include determining, based at least inpart on a number of downlink CCs scheduled for a UE during a reportinginterval, a number of bits to be included in a PUCCH ACK/NAK payload forthe reporting interval. The operation(s) at block 2105 may be performedusing the wireless communication management module 1120, 1220, 1320,1420, 1520, 1620, 1760, 1860, 1984, or 1986 described with reference toFIG. 11, 12, 13, 14, 15, 16, 17, 18, or 19, or the ACK/NAK payload sizedetermination module 1135, 1235, 1335, 1435, 1535, or 1635 describedwith reference to FIG. 11, 12, 13, 14, 15, or 16.

At blocks 2110 and 2115, a format of the PUCCH ACK/NAK may be selectedbased at least in part on the determined number of bits. Moreparticularly, and at block 1610, the method 2100 may include comparingthe number of bits to be included in the PUCCH ACK/NAK payload to aplurality of bit ranges. The operation(s) at block 2110 may be performedusing the wireless communication management module 1120, 1220, 1320,1420, 1520, 1620, 1760, 1860, 1984, or 1986 described with reference toFIG. 11, 12, 13, 14, 15, 16, 17, 18, or 19, or the ACK/NAK payload sizecomparison module 1245 described with reference to FIG. 12.

At block 2115, the method 2100 may include selecting the format of thePUCCH ACK/NAK payload based at least in part on the comparing performedat block 2110. In some examples, the selected format of the PUCCHACK/NAK payload may be based at least in part on a format including tworeference signal symbol periods per slot. The operation(s) at block 2115may be performed using the wireless communication management module1120, 1220, 1320, 1420, 1520, 1620, 1760, 1860, 1984, or 1986 describedwith reference to FIG. 11, 12, 13, 14, 15, 16, 17, 18, or 19, or theACK/NAK payload format selection module 1140, 1240, 1340, 1440, 1540, or1640 described with reference to FIG. 11, 12, 13, 14, 15, or 16.

In some examples of the method 2100, the selected format of the PUCCHACK/NAK payload may be based at least in part on a format including tworeference signal symbol periods per slot (e.g., when the selected formatis for a transmission, in a slot of a subframe, with a normal CP). Insome examples, the selected format of the PUCCH ACK/NAK payload may bebased at least in part on a format including one reference signal symbolperiod per slot (e.g., when the selected format is for a transmission,in a slot of a subframe, with an extended CP).

In some examples of the method 2100, the selected format of the PUCCHACK/NAK payload may include a UE multiplexing density, within a RB, ofat least four UEs (e.g., four or five UEs). Such a format (i.e., a firstformat) may be selected, for example, when the number of bits to beincluded in the ACK/NAK payload is 21 or fewer bits (or from 1 to 21bits) and a RB is configured as described with reference to FIG. 4 or 5.

In some examples of the method 2100, the selected format of the PUCCHACK/NAK payload may include a UE multiplexing density, within a RB, oftwo UEs. The selected format may also include at least two groups ofsymbol periods, where each of the at least two groups of symbol periodsincludes at least one symbol, and where spreading is appliedindependently within each of the at least two groups of symbol periods.Such a format (i.e., a second format) may be selected, for example, whenthe number of bits to be included in the ACK/NAK payload is 60 or fewerbits (or from 22 to 60 bits) and a RB is configured as described withreference to FIG. 4 or 5.

In a first example of the second format, a spreading factor of three maybe applied to a first group of three symbol periods and a spreadingfactor of two may be applied to a second group of two symbol periods,and two of three OCCs may be used when applying the spreading factor ofthree. In a second example of the second format, a first spreadingfactor of two may be applied to a first group of one symbol period, asecond spreading factor of two may be applied to a second group of twosymbol periods, and a third spreading factor of two may be appliedwithin a third group of two symbol periods. In the second example of thesecond format, the first spreading factor may be applied using a Walshcode or using elements of an orthogonal FFT matrix. In a third exampleof the second format, each spreading factor of a plurality of spreadingfactors of two may be applied to a respective symbol period of aplurality of symbol periods. In the third example of the second format,each spreading factor of the plurality of spreading factors of two maybe applied using a Walsh code or using elements of an orthogonal FFTmatrix.

In some examples of the method 2100, the selected format of the PUCCHACK/NAK payload may include no UE multiplexing within a RB, no spreadingfactor, and an RB allocation per symbol period of one. Such a format(i.e., a third format) may be selected, for example, when the number ofbits to be included in the ACK/NAK payload is 120 or fewer bits (or from61 to 120 bits) and a RB is configured as described with reference toFIG. 4 or 5.

In some examples of the method 2100, the selected format of the PUCCHACK/NAK payload may include no UE multiplexing within a RB, no spreadingfactor, and an RB allocation per symbol period of two. Such a format(i.e., a fourth format) may be selected, for example, when the number ofbits to be included in the ACK/NAK payload is 240 or fewer bits (or from121 to 240 bits) and a RB is configured as described with reference toFIG. 4 or 5.

In some examples of the method 2100, the selected format of the PUCCHACK/NAK payload may include no UE multiplexing within a RB, no spreadingfactor, and an RB allocation per symbol period of three. Such a format(i.e., a fifth format) may be selected, for example, when the number ofbits to be included in the ACK/NAK payload is 360 or fewer bits (or from241 to 360 bits) and a RB is configured as described with reference toFIG. 4 or 5.

Thus, the method 2100 may provide for wireless communication. It shouldbe noted that the method 2100 is just one implementation and that theoperations of the method 2100 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 22 is a flow chart illustrating an exemplary method 2200 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2200 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 1715, or 1815 described with reference to FIG. 1, 2, 17, or 18,or aspects of one or more of the apparatuses 1115, 1215, 1315, or 1515described with reference to FIG. 11, 12, 13, or 15. In some examples, aUE or apparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware.

At block 2205, the method 2200 may include identifying an allocation ofa plurality of downlink CCs for a UE. The operation(s) at block 2205 maybe performed using the wireless communication management module 1120,1220, 1320, 1520, 1760, or 1984 described with reference to FIG. 11, 12,13, 15, 17, or 19, or the downlink CC identification module 1345described with reference to FIG. 13.

At block 2210, the method 2200 may include identifying at least a firstsubset of downlink CCs within the plurality of downlink CCs. Additionalsubsets of downlink CCs may also be identified (e.g., a second subset ofdownlink CCs, etc.). The operation(s) at block 2210 may be performedusing the wireless communication management module 1120, 1220, 1320,1520, 1760, or 1984 described with reference to FIG. 11, 12, 13, 15, 17,or 19, or the downlink CC subset identification module 1350 describedwith reference to FIG. 13.

At block 2215, the method 2200 may include determining, based at leastin part on a number of downlink CCs in the first subset of downlink CCsthat are scheduled for the UE during a reporting interval, a number ofbits to be included in a first PUCCH ACK/NAK payload for the reportinginterval. The operation(s) performed at block 2215 may also includedetermining, based at least in part on a number of downlink CCs in eachof one or more additional subsets of downlink CCs that are scheduled forthe UE during a reporting interval (e.g., for the second subset ofdownlink CCs), a number of bits to be included in each of the one ormore additional PUCCH ACK/NAK payloads (e.g., a second PUCCH ACK/NAKpayload) for the reporting interval. The operation(s) at block 2215 maybe performed using the wireless communication management module 1120,1220, 1320, 1520, 1760, or 1984 described with reference to FIG. 11, 12,13, 15, 17, or 19, or the ACK/NAK payload size determination module1135, 1235, 1335, or 1535 described with reference to FIG. 11, 12, 13,or 15.

At block 2220, the method 2200 may include selecting, based at least inpart on the determined number of bits for the first PUCCH ACK/NAKpayload, a format of the first PUCCH ACK/NAK payload. The operation(s)at block 2220 may also include selecting, based at least in part on thedetermined number of bits for the PUCCH ACK/NAK payload(s) of each ofthe one or more additional subsets of downlink CCs (e.g., the secondsubset of downlink CCs), a format of each of the one or more additionalPUCCH ACK/NAK payloads (e.g., the second PUCCH ACK/NAK payload). Theoperation(s) at block 2220 may be performed using the wirelesscommunication management module 1120, 1220, 1320, 1520, 1760, or 1984described with reference to FIG. 11, 12, 13, 15, 17, or 19, or theACK/NAK payload format selection module 1140, 1240, 1340, or 1540described with reference to FIG. 11, 12, 13, or 15.

At block 2225, the method 2200 may include transmitting the first PUCCHACK/NAK payload on a first uplink CC, and transmitting an additionalPUCCH ACK/NAK payload for the reporting interval (e.g., the secondACK/NAK payload) on a second uplink CC. Alternatively, and at block1730, the method 1700 may include transmitting the first PUCCH ACK/NAKpayload and an additional ACK/NAK payload (e.g., the second ACK/NAKpayload) on a same uplink CC. The operation(s) at block 2225 or 2230 maybe performed using the wireless communication management module 1120,1220, 1320, 1520, 1760, or 1984 described with reference to FIG. 11, 12,13, 15, 17, or 19, or the ACK/NAK payload transmission management module1355 described with reference to FIG. 13.

Thus, the method 2200 may provide for wireless communication. It shouldbe noted that the method 2200 is just one implementation and that theoperations of the method 2200 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 23 is a flow chart illustrating an exemplary method 2300 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2300 is described below withreference to aspects of one or more of the base stations 105, 205,205-a, 1805, or 1905 described with reference to FIG. 1, 2, 18, or 19,or aspects of one or more of the apparatuses 1115, 1215, 1415, or 1615described with reference to FIG. 11, 12, 14, or 16. In some examples, abase station or apparatus may execute one or more sets of codes tocontrol the functional elements of the base station or apparatus toperform the functions described below. Additionally or alternatively,the base station or apparatus may perform one or more of the functionsdescribed below using special-purpose hardware.

At block 2305, the method 2300 may include allocating a plurality ofdownlink CCs for a UE. The operation(s) at block 2305 may be performedusing the wireless communication management module 1120, 1220, 1420,1620, 1860, or 1986 described with reference to FIG. 11, 12, 14, 16, 18,or 19, or the downlink CC allocation module 1445 described withreference to FIG. 14.

At block 2310, the method 2300 may include configuring at least twogroups of downlink CCs (e.g., configuring at least a first subset ofdownlink CCs and a second subset of downlink CCs within the plurality ofdownlink CCs). The operation(s) at block 2310 may be performed using thewireless communication management module 1120, 1220, 1420, 1620, 1860,or 1986 described with reference to FIG. 11, 12, 14, 16, 18, or 19, orthe downlink CC subset configuration module 1450 described withreference to FIG. 14.

At block 2315, the method 2300 may include determining, for each groupof downlink CCs, and based at least in part on a number of downlink CCsthat are scheduled for the UE during a reporting interval, a number ofbits to be included in a PUCCH ACK/NAK payload for the group of downlinkCCs for the reporting interval. Thus, for example, a first number ofbits to be included in a first PUCCH ACK/NAK payload for a first groupof downlink CCs may be determined, and a second number of bits to beincluded in a second PUCCH ACK/NAK payload for a second group ofdownlink CCs may be determined. The operation(s) at block 2315 may beperformed using the wireless communication management module 1120, 1220,1420, 1620, 1860, or 1986 described with reference to FIG. 11, 12, 14,16, 18, or 19, or the ACK/NAK payload size determination module 1135,1235, 1435, or 1635 described with reference to FIG. 11, 12, 14, or 16.

At block 2320, the method 2300 may include selecting, for each PUCCHACK/NAK payload, and based at least in part on the determined number ofbits for the PUCCH ACK/NAK payload, a format of the first PUCCH ACK/NAKpayload. That is, a format of a PUCCH ACK/NAK payload may be selectedfor each of the at least two groups of downlink CCs. Also oralternatively, a format of a PUCCH ACK/NAK payload may be selectedconsidering bundling of ACK/NAK bits for the downlink CCs within each ofthe at least two groups of downlink CCs. The operation(s) at block 2320may be performed using the wireless communication management module1120, 1220, 1420, 1620, 1860, or 1986 described with reference to FIG.11, 12, 14, 16, 18, or 19, or the ACK/NAK payload format selectionmodule 1140, 1240, 1440, or 1640 described with reference to FIG. 11,12, 14, or 16.

Thus, the method 2300 may provide for wireless communication. It shouldbe noted that the method 2300 is just one implementation and that theoperations of the method 2300 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 24 is a flow chart illustrating an exemplary method 2400 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2400 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 1715, or 1815 described with reference to FIG. 1, 2, 17, or 18,or aspects of one or more of the apparatuses 1115, 1215, 1315, or 1515described with reference to FIG. 11, 12, 13, or 15. In some examples, aUE or apparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware.

At block 2405, the method 2400 may include receiving, at a UE, a numberof downlink grants indicating the downlink CCs scheduled for the UE, andreceiving with each of the downlink grants a respective DAI. Theoperation(s) at block 2405 may be performed using the wirelesscommunication management module 1120, 1220, 1320, 1520, 1760, or 1984described with reference to FIG. 11, 12, 13, 15, 17, or 19, or thedownlink grant processing module 1545 or DAI processing module 1550described with reference to FIG. 15.

At block 2410, the method 2400 may include determining, based at leastin part on the number of downlink CCs scheduled for the UE during areporting interval, a number of bits to be included in a PUCCH ACK/NAKpayload for the reporting interval. The operation(s) at block 2410 maybe performed using the wireless communication management module 1120,1220, 1320, 1520, 1760, or 1984 described with reference to FIG. 11, 12,13, 15, 17, or 19, or the ACK/NAK payload size determination module1135, 1235, 1335, or 1535 described with reference to FIG. 11, 12, 13,or 15.

At block 2415, the method 2400 may include selecting, based at least inpart on the determined number of bits, a format of the PUCCH ACK/NAKpayload. The operation(s) at block 2415 may be performed using thewireless communication management module 1120, 1220, 1320, 1520, 1760,or 1984 described with reference to FIG. 11, 12, 13, 15, 17, or 19, orthe ACK/NAK payload format selection module 1140, 1240, 1340, or 1540described with reference to FIG. 11, 12, 13, or 15.

In some examples of the method 2400, the respective DAI for a downlinkgrant may indicate a bit mapping and resource selection, in the PUCCHACK/NAK payload, for acknowledging/non-acknowledging each transmissionover each downlink CC scheduled in the downlink grant.

In some examples of the method 2400, the respective DAI for a downlinkgrant may include a sequence number indicating a relationship between atleast one downlink CC scheduled in the downlink grant and at least onedownlink CC scheduled in another downlink grant. In these examples, themethod 2400 may further include determining, based at least in part onthe sequence number, a bit mapping and resource selection, in the PUCCHACK/NAK payload, for acknowledging/non-acknowledging each transmissionover each downlink CC scheduled in the downlink grant.

Thus, the method 2400 may provide for wireless communication. It shouldbe noted that the method 2400 is just one implementation and that theoperations of the method 2400 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 25 is a flow chart illustrating an exemplary method 2500 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2500 is described below withreference to aspects of one or more of the base stations 105, 205,205-a, 1805, or 1905 described with reference to FIG. 1, 2, 18, or 19,or aspects of one or more of the apparatuses 1115, 1215, 1415, or 1615described with reference to FIG. 11, 12, 14, or 16. In some examples, abase station or apparatus may execute one or more sets of codes tocontrol the functional elements of the base station or apparatus toperform the functions described below. Additionally or alternatively,the base station or apparatus may perform one or more of the functionsdescribed below using special-purpose hardware.

At block 2505, the method 2500 may include transmitting, from a basestation to a UE, a plurality of downlink grants indicating the downlinkCCs scheduled for the UE, and transmitting a plurality of DAIs, whereeach of the plurality of downlink grants includes a respective one ofthe DAIs in the plurality of DAIs. The operation(s) at block 2505 may beperformed using the wireless communication management module 1120, 1220,1420, 1620, 1860, or 1986 described with reference to FIG. 11, 12, 14,16, 18, or 19, or the downlink grant transmission management module 1645or DAI transmission management module 1655 described with reference toFIG. 16.

At block 2510, the method 2500 may include determining, based at leastin part on the number of downlink CCs scheduled for the UE during areporting interval, a number of bits to be included in a PUCCH ACK/NAKpayload for the reporting interval. The operation(s) at block 2510 maybe performed using the wireless communication management module 1120,1220, 1420, 1620, 1860, or 1986 described with reference to FIG. 11, 12,14, 16, 18, or 19, or the ACK/NAK payload size determination module1135, 1235, 1435, or 1635 described with reference to FIG. 11, 12, 14,or 16.

At block 2515, the method 2500 may include selecting, based at least inpart on the determined number of bits, a format of the PUCCH ACK/NAKpayload. The operation(s) at block 2515 may be performed using thewireless communication management module 1120, 1220, 1420, 1620, 1860,or 1986 described with reference to FIG. 11, 12, 14, 16, 18, or 19, orthe ACK/NAK payload format selection module 1140, 1240, 1440, or 1640described with reference to FIG. 11, 12, 14, or 16.

In some examples of the method 2500, the respective DAI for a downlinkgrant may indicate a bit mapping and resource selection, in the PUCCHACK/NAK payload, for acknowledging/non-acknowledging each transmissionover each downlink CC scheduled in the downlink grant.

In some examples of the method 2500, the plurality of DAIs may include aplurality of sequence numbers. In these examples, the method 2500 mayfurther include introducing sequence discontinuities in the plurality ofsequence numbers, to increase the number of bits to be included in thePUCCH ACK/NAK payload. The method 2500 may also include receiving thePUCCH ACK/NAK payload and using a set of ACK/NAK bits in the PUCCHACK/NAK payload, which set of ACK/NAK bits correspond to the sequencediscontinuities, as a virtual CRC. In some examples, sequencediscontinuities may be introduced in the plurality of sequence numbersto both increase the number of bits to be included in the PUCCH ACK/NAKpayload and to increase the length of the virtual CRC.

Thus, the method 2500 may provide for wireless communication. It shouldbe noted that the method 2500 is just one implementation and that theoperations of the method 2500 may be rearranged or otherwise modifiedsuch that other implementations are possible.

In some examples, aspects of two or more of the methods 2000, 2100,2200, or 2400 described with reference to FIG. 20, 21, 22, or 24 may becombined, or aspects of two or more of the methods 2000, 2100, 2300, or2500 described with reference to FIG. 20, 21, 23, or 25 may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, andother systems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Aare commonly referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) iscommonly referred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD),etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. ATDMA system may implement a radio technology such as Global System forMobile Communications (GSM). An OFDMA system may implement a radiotechnology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA),IEEE 802.11 (WiFi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM™, etc.UTRA and E-UTRA are part of Universal Mobile Telecommunication System(UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are newreleases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, andGSM are described in documents from an organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies, including cellular (e.g., LTE) communicationsover an unlicensed and/or shared bandwidth. The description above,however, describes an LTE/LTE-A system for purposes of example, and LTEterminology is used in much of the description above, although thetechniques are applicable beyond LTE/LTE-A applications.

The detailed description set forth above in connection with the appendeddrawings describes examples and does not represent the only examplesthat may be implemented or that are within the scope of the claims. Theterms “example” and “exemplary,” when used in this description, mean“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other examples.” The detailed description includesspecific details for the purpose of providing an understanding of thedescribed techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand apparatuses are shown in block diagram form in order to avoidobscuring the concepts of the described examples.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, anFPGA or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, or any combination thereof designedto perform the functions described herein. A general-purpose processormay be a microprocessor, but in the alternative, the processor may beany conventional processor, controller, microcontroller, or statemachine. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor,multiple microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these.

Features implementing functions may also be physically located atvarious positions, including being distributed such that portions offunctions are implemented at different physical locations. As usedherein, including in the claims, the term “and/or,” when used in a listof two or more items, means that any one of the listed items can beemployed by itself, or any combination of two or more of the listeditems can be employed. For example, if a composition is described ascontaining components A, B, and/or C, the composition can contain Aalone; B alone; C alone; A and B in combination; A and C in combination;B and C in combination; or A, B, and C in combination. Also, as usedherein, including in the claims, “or” as used in a list of items (forexample, a list of items prefaced by a phrase such as “at least one of”or “one or more of”) indicates a disjunctive list such that, forexample, a list of “at least one of A, B, or C” means A or B or C or ABor AC or BC or ABC (i.e., A and B and C).

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media cancomprise RAM, ROM, EEPROM, flash memory, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother non-transitory medium that can be used to carry or store desiredprogram code means in the form of instructions or data structures andthat can be accessed by a general-purpose or special-purpose computer,or a general-purpose or special-purpose processor. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the scope of thedisclosure. Thus, the disclosure is not to be limited to the examplesand designs described herein but is to be accorded the broadest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A method for wireless communication, comprising:determining, based at least in part on a number of downlink componentcarriers (CCs) scheduled for a user equipment (UE) during a reportinginterval, a number of bits to be included in a physical uplink controlchannel (PUCCH) acknowledgement/non-acknowledgement (ACK/NAK) payloadfor the reporting interval; and selecting, based at least in part on thedetermined number of bits, a format of the PUCCH ACK/NAK payload.
 2. Themethod of claim 1, wherein selecting the format of the PUCCH ACK/NAKpayload comprises: selecting one of a plurality of predefined formatsfor the PUCCH ACK/NAK payload, wherein the predefined formats for thePUCCH ACK/NAK payload comprise different combinations of: UEmultiplexing densities within a resource block (RB), spreading factors,or numbers of RBs allocated per symbol period.
 3. The method of claim 2,wherein each of the predefined formats for the PUCCH ACK/NAK payload isbased at least in part on a format comprising two reference signalsymbol periods per slot.
 4. The method of claim 1, wherein the selectedformat of the PUCCH ACK/NAK payload is based at least in part on aformat comprising two reference signal symbol periods per slot.
 5. Themethod of claim 1, wherein the selected format of the PUCCH ACK/NAKpayload is further based at least in part on a format comprising onereference signal symbol per slot.
 6. The method of claim 1, whereinselecting the format of the PUCCH ACK/NAK payload comprises: comparingthe number of bits to be included in the PUCCH ACK/NAK payload to aplurality of bit ranges; and selecting the format of the PUCCH ACK/NAKpayload based at least in part on the comparing.
 7. The method of claim6, wherein the selected format of the PUCCH ACK/NAK payload comprises: aUE multiplexing density, within a RB, of at least four UEs.
 8. Themethod of claim 6, wherein the selected format of the PUCCH ACK/NAKpayload comprises: a UE multiplexing density, within a RB, of two UEs;and at least two groups of symbol periods, wherein each of the at leasttwo groups of symbol periods comprises at least one symbol, and whereinspreading is applied independently within each of the at least twogroups of symbol periods.
 9. The method of claim 8, wherein a spreadingfactor of three is applied to a first group of three symbol periods anda spreading factor of two is applied to a second group of two symbolperiods, and wherein two of three orthogonal cover codes (OCCs) are usedwhen applying the spreading factor of three.
 10. The method of claim 8,wherein a first spreading factor of two is applied to a first group ofone symbol period, a second spreading factor of two is applied to asecond group of two symbol periods, and a third spreading factor of twois applied to a third group of two symbol periods.
 11. The method ofclaim 10, wherein the first spreading factor is applied using a Walshcode or using elements of an orthogonal Fast Fourier Transform (FFT)matrix.
 12. The method of claim 8, wherein each spreading factor of aplurality of spreading factors of two is applied to a respective symbolperiod of a plurality of symbol periods.
 13. The method of claim 12,wherein each spreading factor of the plurality of spreading factors oftwo is applied using a Walsh code or using elements of an orthogonal FFTmatrix.
 14. The method of claim 6, wherein the selected format of thePUCCH ACK/NAK payload comprises: no UE multiplexing within a RB; nospreading factor; and a RB allocation per symbol period of one.
 15. Themethod of claim 6, wherein the selected format of the PUCCH ACK/NAKpayload comprises: no UE multiplexing within a RB; no spreading factor;and a RB allocation per symbol period of two.
 16. The method of claim 6,wherein the selected format of the PUCCH ACK/NAK payload comprises: noUE multiplexing within a RB; no spreading factor; and a RB allocationper symbol period of three.
 17. The method of claim 1, furthercomprising: identifying an allocation of a plurality of downlink CCs forthe UE; and identifying a first subset of downlink CCs within theplurality of downlink CCs; wherein the number of bits to be included inthe PUCCH ACK/NAK payload is identified for the first subset of downlinkCCs.
 18. The method of claim 17, wherein the PUCCH ACK/NAK payloadcomprises a first PUCCH ACK/NAK payload, the method further comprising:identifying a second subset of downlink CCs within the plurality ofdownlink CCs, wherein the second subset of downlink CCs corresponds to asecond PUCCH ACK/NAK payload.
 19. The method of claim 18, furthercomprising: transmitting the first PUCCH ACK/NAK payload on a firstuplink CC; and transmitting the second PUCCH ACK/NAK payload on a seconduplink CC.
 20. The method of claim 18, further comprising: transmittingthe first PUCCH ACK/NAK payload and the second PUCCH ACK/NAK payload ona same uplink CC.
 21. The method of claim 1, further comprising:receiving, at the UE, a number of downlink grants indicating thedownlink CCs scheduled for the UE; and receiving with each of thedownlink grants a respective downlink assignment index (DAI).
 22. Themethod of claim 21, wherein the respective DAI for a downlink grantindicates a bit mapping and resource selection, in the PUCCH ACK/NAKpayload, for acknowledging/non-acknowledging each transmission over eachdownlink CC scheduled in the downlink grant.
 23. The method of claim 21,wherein the respective DAI for a downlink grant comprises a sequencenumber indicating a relationship between at least one downlink CCscheduled in the downlink grant and at least one downlink CC scheduledin another downlink grant, the method further comprising: determining,based at least in part on the sequence number, a bit mapping andresource selection, in the PUCCH ACK/NAK payload, foracknowledging/non-acknowledging each transmission over each downlink CCscheduled in the downlink grant.
 24. The method of claim 1, furthercomprising: transmitting, from a base station to the UE, a plurality ofdownlink grants indicating the downlink CCs scheduled for the UE; andtransmitting a plurality of DAIS, wherein each of the plurality ofdownlink grants includes a respective one of the DAIS in the pluralityof DAIS.
 25. The method of claim 24, wherein the plurality of DAIScomprise a plurality of sequence numbers, the method further comprising:introducing sequence discontinuities in the plurality of sequencenumbers, to increase the number of bits to be included in the PUCCHACK/NAK payload.
 26. The method of claim 25, further comprising:receiving the PUCCH ACK/NAK payload; and using a set of ACK/NAK bits inthe PUCCH ACK/NAK payload, which set of ACK/NAK bits correspond to thesequence discontinuities, as a virtual cyclic redundancy check (CRC).27. The method of claim 1, further comprising: receiving, at the UE, anACK/NAK resource indicator (ARI) identifying at least two differentuplink CCs.
 28. The method of claim 1, further comprising: receiving, atthe UE, a number of downlink grants indicating the downlink CCsscheduled for the UE; wherein selecting the format of the PUCCH ACK/NAKpayload comprises selecting a format used to transmit the PUCCH ACK/NAKpayload.
 29. The method of claim 1, further comprising: transmitting,from a base station to the UE, a plurality of downlink grants indicatingthe downlink CCs scheduled for the UE; wherein selecting the format ofthe PUCCH ACK/NAK payload comprises selecting a format used to decodethe PUCCH ACK/NAK payload.
 30. The method of claim 1, furthercomprising: configuring at least two groups of downlink CCs, whereinselecting the format of the PUCCH ACK/NAK payload is performed for eachof the at least two groups of downlink CCs.
 31. The method of claim 1,further comprising: configuring at least two groups of downlink CCs,wherein selecting the format of the PUCCH ACK/NAK payload is performedconsidering bundling of ACK/NAK bits for the downlink CCs within eachgroup of downlink CCs.
 32. An apparatus for wireless communication,comprising: means for determining, based at least in part on a number ofdownlink component carriers (CCs) scheduled for a user equipment (UE)during a reporting interval, a number of bits to be included in aphysical uplink control channel (PUCCH)acknowledgement/non-acknowledgement (ACK/NAK) payload for the reportinginterval; and means for selecting, based at least in part on thedetermined number of bits, a format of the PUCCH ACK/NAK payload. 33.The apparatus of claim 32, wherein the means for selecting the format ofthe PUCCH ACK/NAK payload comprises: means for selecting one of aplurality of predefined formats for the PUCCH ACK/NAK payload, whereinthe predefined formats for the PUCCH ACK/NAK payload comprise differentcombinations of: UE multiplexing densities within a resource block (RB),spreading factors, or numbers of RBs allocated per symbol period. 34.The apparatus of claim 33, wherein each of the predefined formats forthe PUCCH ACK/NAK payload is based at least in part on a formatcomprising two reference signal symbol periods per slot.
 35. Theapparatus of claim 32, wherein the selected format of the PUCCH ACK/NAKpayload is based at least in part on a format comprising two referencesignal symbol periods per slot.
 36. The apparatus of claim 32, whereinthe selected format of the PUCCH ACK/NAK payload is further based atleast in part on a format comprising one reference signal symbol perslot.
 37. The apparatus of claim 32, wherein selecting the format of thePUCCH ACK/NAK payload comprises: means for comparing the number of bitsto be included in the PUCCH ACK/NAK payload to a plurality of bitranges; and means for selecting the format of the PUCCH ACK/NAK payloadbased at least in part on the comparing.
 38. The apparatus of claim 37,wherein the selected format of the PUCCH ACK/NAK payload comprises: a UEmultiplexing density, within a RB, of at least four UEs.
 39. Theapparatus of claim 37, wherein the selected format of the PUCCH ACK/NAKpayload comprises: a UE multiplexing density, within a RB, of two UEs;and at least two groups of symbol periods, wherein each of the at leasttwo groups of symbol periods comprises at least one symbol, and whereinspreading is applied independently within each of the at least twogroups of symbol periods.
 40. The apparatus of claim 39, wherein aspreading factor of three is applied to a first group of three symbolperiods and a spreading factor of two is applied to a second group oftwo symbol periods, and wherein two of three orthogonal cover codes(OCCs) are used when applying the spreading factor of three.
 41. Theapparatus of claim 39, wherein a first spreading factor of two isapplied to a first group of one symbol period, a second spreading factorof two is applied to a second group of two symbol periods, and a thirdspreading factor of two is applied to a third group of two symbolperiods.
 42. The apparatus of claim 41, wherein the first spreadingfactor is applied using a Walsh code or using elements of an orthogonalFast Fourier Transform (FFT) matrix.
 43. The apparatus of claim 39,wherein each spreading factor of a plurality of spreading factors of twois applied to a respective symbol period of a plurality of symbolperiods.
 44. The apparatus of claim 43, wherein each spreading factor ofthe plurality of spreading factors of two is applied using a Walsh codeor using elements of an orthogonal FFT matrix.
 45. The apparatus ofclaim 37, wherein the selected format of the PUCCH ACK/NAK payloadcomprises: no UE multiplexing within a RB; no spreading factor; and a RBallocation per symbol period of one.
 46. The apparatus of claim 37,wherein the selected format of the PUCCH ACK/NAK payload comprises: noUE multiplexing within a RB; no spreading factor; and a RB allocationper symbol period of two.
 47. The apparatus of claim 37, wherein theselected format of the PUCCH ACK/NAK payload comprises: no UEmultiplexing within a RB; no spreading factor; and a RB allocation persymbol period of three.
 48. The apparatus of claim 32, furthercomprising: means for identifying an allocation of a plurality ofdownlink CCs for the UE; and means for identifying a first subset ofdownlink CCs within the plurality of downlink CCs; wherein the number ofbits to be included in the PUCCH ACK/NAK payload is identified for thefirst subset of downlink CCs.
 49. The apparatus of claim 48, wherein thePUCCH ACK/NAK payload comprises a first PUCCH ACK/NAK payload, theapparatus further comprising: means for identifying a second subset ofdownlink CCs within the plurality of downlink CCs, wherein the secondsubset of downlink CCs corresponds to a second PUCCH ACK/NAK payload.50. The apparatus of claim 49, further comprising: means fortransmitting the first PUCCH ACK/NAK payload on a first uplink CC; andmeans for transmitting the second PUCCH ACK/NAK payload on a seconduplink CC.
 51. The apparatus of claim 49, further comprising: means fortransmitting the first PUCCH ACK/NAK payload and the second PUCCHACK/NAK payload on a same uplink CC.
 52. The apparatus of claim 32,further comprising: means for receiving, at the UE, a number of downlinkgrants indicating the downlink CCs scheduled for the UE; and means forreceiving with each of the downlink grants a respective downlinkassignment index (DAI).
 53. The apparatus of claim 52, wherein therespective DAI for a downlink grant indicates a bit mapping and resourceselection, in the PUCCH ACK/NAK payload, foracknowledging/non-acknowledging each transmission over each downlink CCscheduled in the downlink grant.
 54. The apparatus of claim 52, whereinthe respective DAI for a downlink grant comprises a sequence numberindicating a relationship between at least one downlink CC scheduled inthe downlink grant and at least one downlink CC scheduled in anotherdownlink grant, the apparatus further comprising: means for determining,based at least in part on the sequence number, a bit mapping andresource selection, in the PUCCH ACK/NAK payload, foracknowledging/non-acknowledging each transmission over each downlink CCscheduled in the downlink grant.
 55. The apparatus of claim 32, furthercomprising: means for transmitting, from a base station to the UE, aplurality of downlink grants indicating the downlink CCs scheduled forthe UE; and means for transmitting a plurality of DAIS, wherein each ofthe plurality of downlink grants includes a respective one of the DAISin the plurality of DAIS.
 56. The apparatus of claim 55, wherein theplurality of DAIS comprise a plurality of sequence numbers, theapparatus further comprising: means for introducing sequencediscontinuities in the plurality of sequence numbers, to increase thenumber of bits to be included in the PUCCH ACK/NAK payload.
 57. Theapparatus of claim 56, further comprising: means for receiving the PUCCHACK/NAK payload; and means for using a set of ACK/NAK bits in the PUCCHACK/NAK payload, which set of ACK/NAK bits correspond to the sequencediscontinuities, as a virtual cyclic redundancy check (CRC).
 58. Theapparatus of claim 32, further comprising: means for receiving, at theUE, an ACK/NAK resource indicator (ARI) identifying at least twodifferent uplink CCs.
 59. The apparatus of claim 32, further comprising:means for receiving, at the UE, a number of downlink grants indicatingthe downlink CCs scheduled for the UE; wherein the means for selectingthe format of the PUCCH ACK/NAK payload comprises means for selecting aformat used to transmit the PUCCH ACK/NAK payload.
 60. The apparatus ofclaim 32, further comprising: means for transmitting, from a basestation to the UE, a plurality of downlink grants indicating thedownlink CCs scheduled for the UE; wherein the means for selecting theformat of the PUCCH ACK/NAK payload comprises means for selecting aformat used to decode the PUCCH ACK/NAK payload.
 61. The apparatus ofclaim 32, further comprising: means for configuring at least two groupsof downlink CCs, wherein selecting the format of the PUCCH ACK/NAKpayload is performed for each of the at least two groups of downlinkCCs.
 62. The apparatus of claim 32, further comprising: means forconfiguring at least two groups of downlink CCs, wherein selecting theformat of the PUCCH ACK/NAK payload is performed considering bundling ofACK/NAK bits for the downlink CCs within each group of downlink CCs. 63.An apparatus for wireless communication, comprising: a processor; memoryin electronic communication with the processor; and instructions storedin the memory, the instructions being executable by the processor to:determine, based at least in part on a number of downlink componentcarriers (CCs) scheduled for a user equipment (UE) during a reportinginterval, a number of bits to be included in a physical uplink controlchannel (PUCCH) acknowledgement/non-acknowledgement (ACK/NAK) payloadfor the reporting interval; and select, based at least in part on thedetermined number of bits, a format of the PUCCH ACK/NAK payload. 64.The apparatus of claim 63, wherein the instructions executable by theprocessor to select the format of the PUCCH ACK/NAK payload compriseinstructions executable by the processor to: select one of a pluralityof predefined formats for the PUCCH ACK/NAK payload, wherein thepredefined formats for the PUCCH ACK/NAK payload comprise differentcombinations of: UE multiplexing densities within a resource block (RB),spreading factors, or numbers of RBs allocated per symbol period. 65.The apparatus of claim 63, wherein the selected format of the PUCCHACK/NAK payload is based at least in part on a format comprising tworeference signal symbol periods per slot.
 66. The apparatus of claim 63,wherein the selected format of the PUCCH ACK/NAK payload is furtherbased at least in part on a format comprising one reference signalsymbol per slot.
 67. The apparatus of claim 63, wherein the instructionsexecutable by the processor to select the format of the PUCCH ACK/NAKpayload comprise instructions executable by the processor to: comparethe number of bits to be included in the PUCCH ACK/NAK payload to aplurality of bit ranges; and select the format of the PUCCH ACK/NAKpayload based at least in part on the comparing.
 68. The apparatus ofclaim 63, wherein the instructions are executable by the processor to:identify an allocation of a plurality of downlink CCs for the UE; andidentify a first subset of downlink CCs within the plurality of downlinkCCs; wherein the number of bits to be included in the PUCCH ACK/NAKpayload is identified for the first subset of downlink CCs.
 69. Theapparatus of claim 63, wherein the instructions are executable by theprocessor to: receive, at the UE, a number of downlink grants indicatingthe downlink CCs scheduled for the UE; and receive with each of thedownlink grants a respective downlink assignment index (DAI).
 70. Theapparatus of claim 63, wherein the instructions are executable by theprocessor to: transmit, from a base station to the UE, a plurality ofdownlink grants indicating the downlink CCs scheduled for the UE; andtransmit a plurality of DAIS, wherein each of the plurality of downlinkgrants includes a respective one of the DAIS in the plurality of DAIS.71. The apparatus of claim 63, wherein the instructions are executableby the processor to: configure at least two groups of downlink CCs,wherein selecting the format of the PUCCH ACK/NAK payload is performedfor each of the at least two groups of downlink CCs.
 72. The apparatusof claim 63, wherein the instructions are executable by the processorto: configure at least two groups of downlink CCs, wherein selecting theformat of the PUCCH ACK/NAK payload is performed considering bundling ofACK/NAK bits for the downlink CCs within each group of downlink CCs. 73.A computer program product comprising a non-transitory computer-readablemedium, the non-transitory computer-readable medium comprising:instructions to determine, based at least in part on a number ofdownlink component carriers (CCs) scheduled for a user equipment (UE)during a reporting interval, a number of bits to be included in aphysical uplink control channel (PUCCH)acknowledgement/non-acknowledgement (ACK/NAK) payload for the reportinginterval; and instructions to select, based at least in part on thedetermined number of bits, a format of the PUCCH ACK/NAK payload. 74.The computer program product of claim 73, wherein the instructions toselect the format of the PUCCH ACK/NAK payload comprise: instructions toselect one of a plurality of predefined formats for the PUCCH ACK/NAKpayload, wherein the predefined formats for the PUCCH ACK/NAK payloadcomprise different combinations of: UE multiplexing densities within aresource block (RB), spreading factors, or numbers of RBs allocated persymbol period.
 75. The computer program product of claim 73 wherein theinstructions to select the format of the PUCCH ACK/NAK payload comprise:instructions to compare the number of bits to be included in the PUCCHACK/NAK payload to a plurality of bit ranges; and instructions to selectthe format of the PUCCH ACK/NAK payload based at least in part on thecomparing.
 76. The computer program product of claim 73, furthercomprising: instructions to identify an allocation of a plurality ofdownlink CCs for the UE; and instructions to identify a first subset ofdownlink CCs within the plurality of downlink CCs; wherein the number ofbits to be included in the PUCCH ACK/NAK payload is identified for thefirst subset of downlink CCs.